Moto Yakuza ga BL Sakka ni Nattarashii
To be or not to be
Reminds me a lot of my personal favourite danmei novel, Scum Villain's Self Saving System. Though it's not a teacher-student relationship, and more of a enemies-to-lovers kind of story. In the original story, the emperor was to die by the main character's hand for locking the MC up after the previous emperor destroyed the MC's home kingdom. But when the main character transmigrates into the emperor's body and finds the MC locked in his prison, he tries to do everything he can to kiss his ass so he survives... but he ends up having the MC wanting to literally kiss his ass instead. (lol) Spoiler for the second half of the story: It's a little jarring, but I personally liked this part of the story. The first half has us following Xiao Yu'an, the emperor, who is rather effeminate and delicate looking, but very different from the body that the transmigrator came from. After certain events, the transmigrator wakes up in a body that is far more similar to himself, with a background and features that are more accurate to him. It gives the main character a chance to confirm his feelings for the existence of [Xiao Yu'an] further, no matter his appearance.
To Make A Delicious Omega Squeak