I've been trying to look for a novel which I've forgotten the title of and can only vaguely remember the plot. I've tried looking through as many tags as applicable but couldn't find it. At this point, the only reason why I'm sure I didn't dream it up is because I know I can't write to save my life. MC made a contract with ML to deal with his "needs" (either ABO or guide verse). ML then misunderstands and disdains MC for not looking after his health but is actually being abused by ML's servants without the latter knowing. By the time ML realizes that MC was being abused and not actually neglecting himself, MC was already mentally broken and suicidal. After that ML tries to make things right and punish the servants and goes on a long rocky road to recovery with MC. The most memorable part was where MC tries to commit suicide by walking onto a fragile frozen lake but was saved by ML before he could step on it.