That Time the School Bully Rescued Me Again and Again, but I Didn't Want Him To
Chen Jin walked down that street as usual. He knew the little thug who often bullied him would be there, demanding some inexplicable protection money every month.
Then one day, another thug showed up and broke the peace. Not only did he step in to stop it all, he also said he was doing it for justice. Most importantly, he openly announced his family name: Lu Tian.
Chen Jin was speechless. He knew this guy: a notorious troublemaker at school, a chuunibyo, and, oh, a bleeding heart too.
After that, he didn't feel grateful to Lu Tian. In fact, he rather disliked him. He hated idiots like that and was already wondering what sort of punishment he'd have to put up with the next day.
Later, for no apparent reason, they became deskmates, and then, for no apparent reason, they became lovers.
Chen Jin thought life really was full of inexplicable things. Someone he'd once disliked had become his lover, and they had even sworn to stay together forever.
Theme: Study hard and keep improving.