My Favorite Manga.

This one is kind of dark. "Efforts never betray". Is what his father would say as he abused his child. Eventually the child became obsessed with perfection and slowly began to lose himself untill there was nothing left. That's when the #1 student comes and attempts to save him but eventually the abused little boy lost himself completely and killed himself because he was so overwhelmed by his father's expectations.

A trained mercenary finally goes home to his family and protects his little sister from bullies.

Tsundere boyfriend who's secretly obsessed with his girlfriend.