I need help, I'm looking for a manga / manhwa yaoi (can't remember which one). It is about a university professor that his partner break up with him during after a long term relationship, he is devastated and when he returns to work the younger brother of his ex is now attending the same university and became his student.

(The younger brother has an obsession to look like his older brother. And I think the author used Western names).

Never Good Enough
CTK

OMG Thank you!