When the mushroom spirit innocently reveals that he's still intent on eventually leaving the palace (and therefore the emperor) for a mountain wilderness where he can cultivate, the emperor steals blood from him while he's asleep and goes to a priest to use magic to secretly bind the mushroom to him in chapter 18. The priest gives him three options: A spell that will bind the mushroom to within 100 steps of the emperor, a spell that traps the mushroom inside a magical artifact and controls him, or a spell that links the emperor's mind to the mushroom so no matter what the mushroom does or where he goes, the emperor knows everything.

And I'm just like, WOW. Did not expect this story to go that dark. Mind you, I think I was just personally weirded out here, and other readers may not find it particularly dark, especially if you're reading on the fly and don't think too much about it.

Which spell he chooses remains a mystery until chapter 22, where it seems like he chose to have the priest make one of the spells that keeps the mushroom near to him—however, the spell was kept in reserve for him to use if he felt like the mushroom was going to actually leave him, rather than being implemented on the spot.

Ultimately, if reluctantly, he decides not to use the spell and grudgingly lets the mushroom go off to cultivate. But he doesn't get rid of the spell either.

Then in chapter 28, it's revealed that actually the emperor had the priest make him all three spells and he was going to use all of them on the mushroom. WTF. The emperor actually confesses this to the mushroom sometime after they confirm their feelings for each other and were planning their marriage ceremony, wherein the emperor takes the mushroom to the artificial forest-garden in the palace that he had built specifically to imprison the mushroom after using the spells on him and confesses about the monk and spells and his original dark intentions for creating this lovely faux-wilderness in the middle of the palace.

The mushroom, because he is both naïve and s*upid although the story is trying its hardest to portray him as innocent, then tells the emperor: "'I think everyone occasionally has a few negative thoughts, but just having those thoughts doesn't make someone a bad person. Sometimes I also think about doing bad things, but I'm still a good mushroom.'" (Chapter 28)

Like, okay, look, that's all very true and very wise and sensible on its own. But this guy stole blood from you while you were sleeping, had a priest make him three separate spells to ens*ave and bind you to him, and built a prison in which to keep you near to him for his own convenience. That is a hell of a lot more than having "a few negative thoughts". Those are explicit and concrete actions he took toward a terrible purpose, and I don't really think you should be giving him credit for not taking the last step to fulfill said terrible purpose and excusing his prior actions. And no, being like "wow but it's such a big and beautiful prison crafted for me just the way I like it, I'm totally going to live here in the future, you were so thoughtful in crafting this prison for me!" doesn't make it any better.

Incidentally, as far as I recall, the story never mentions the emperor actually getting rid of those spells. I guess it's supposed to be implied that he did because he doesn't need them anymore, between the mushroom totally excusing/forgiving him and telling him they'll always be together forever no matter what. But the fact that the story doesn't mention discarding the spells is kind of weird and makes me be like, Hmm, even though I know it's probably just an oversight by the author or an oversight by me missing a one-liner somewhere.

Man, it was going pretty cute up until that point. Color me disappointed. I was enjoying the cliché-but-still-cute dynamic when this happened, and it apparently crossed the line for me. In a story with a toxic romance or yandere ML or the like, I wouldn't bat an eye, but I wasn't expecting this in my fluff and so found it particularly jarring and off-putting. It was also kind out of nowhere because the ML didn't seem like he'd go that far, as his character until then had been generically predictable, like he clearly didn't want the mushroom to leave and was doing his best to persuade and tempt him not to, but honestly I thought the worst he'd do would be to just straight order the mushroom not to leave or threaten to smash his flowerpot again, not plan to ens*ave and imprison him.

I think I wouldn't have gotten such a bad taste in my mouth if the emperor had ONLY gone to the monk and asked about spell options to keep the mushroom with him, and didn't take the mushroom's blood and have the spells made; the story could have still been ambiguous about whether he had chosen a spell, and the much-less-problematic reveal could have been, "I asked a monk about magical ways to keep you with me and he gave me these options, and I admit I was tempted, but I refused them all because I wanted you to be free to make your own choices." Like, if it had just been him having thoughts and exploring shady options without taking concrete action, I wouldn't have found it so off-putting. Even making the prison-garden would have been fine since the story kind of styled it like he was crafting a forest-space to entice the mushroom to stay, only to later have him explicitly state, nah, I was gonna lock you up in there.

I didn't like how the s*xual (implied) scene came across as more forceful at the end. I always feel uneasy when a character insists on something s*xual when the other person isn't interested, is complaining, or is too tired. I wish they had chosen a different direction. It's a short moment that most people might not mind, but it made me slightly uncomfortable.

MC is naive but eager to understand more about how the world works, as well as eager to get to know the ML on a deeper level. He tries his best to understand both what's said and what isn't, even if he misses the point sometimes, always keeping his belief that ML is a good person at heart.

ML is moved by MC's soft heart and native mind. He thinks of himself as a bad person, having done bad things, but wants to protect both MC and the view MC has of him. He's aware of the power he hold over MC to break him, but despite his unwanted thoughts and actions maybe a bit too far, he never let's it get to MC.

ML has had the expected tough past of an upcoming emperor with exposure to violence and usage of it. He feels that he's a bad person because he kills, but MC doesn't analyze it in a complex way and sees it simply as that punishing someone who's done something wrong is does not automatically make someone a bad person. ML can't hesitates to take MC's pure hand in his blood stained ones, but MC is not concerned witnessing spilled blood, but by ML feeling sad as a consequence of it. ML's afraid of scaring MC, but ML truly doesn't understand of think that he has anything to be scared about. Although MC wanted him to stay so desperately that he came up with options to trap him, he never followed through and that says everything there is to know about his character. He also clearly communicates it to MC after reuniting, he did it because of love and didn't follow through because of the same love.

Rather than wanting MC to stay, ML wants MC to want to stay - clear difference. In the end, the option is up to MC. It's strongly felt how much ML doesn't want ML to leave, a bittersweet feeling that ML could' be let go of his grasp in any moment of he just decided to. In the beginning, MC didn't underhand why talking about leaving, or showing that he could leave without any warning or a chance to say goodbye, would be hurtful to MC. MC has never wanted to hurt ML, rather he wants to understand ML so he avoid hurting him.

The letter not being delivered, ML waiting for days after thinking MC happily let him follow him and skip away to never seem him again after saying goodbye, is exactly the type of angst I love. Knowing everything will be fine, misunderstandings that are cleared up by healthy communication.