The Disciple I Picked Up Is the Villain [Book Transmigration]

Basically, it's an age-gap story where the obedient disciple you've raised suddenly develops inappropriate feelings for you, and has been hiding them very well. [Still working on the blurb]

A scheming, calculating gong who lays a careful trap for his master X a cool, reserved, abstinent shou who only wants to dutifully complete his task, but gets played instead

Cover art used with permission: Yi Ye Shu, Lu Shan

Theme: Still thinking