Rito Yuuki is the main protagonist of To Love-Ru. A pretty average brown-haired high school student at Sainan High, he's defined by two things: his hopeless crush on Haruna Sairenji and his equally hopeless ability to stay out of awkward situations with girls.
He's been trying to confess to Haruna for ages without success. Back in junior high he was actually a decent soccer player, but quit the team to help his manga artist father and look after his little sister Mikan. These days he's known for being weirdly good at useless stuff—crane games, carnival games, you name it. Surprisingly, he's also genuinely skilled at gardening and floristry, which doesn't exactly fit his clumsy image.
Speaking of clumsy: Rito's clumsiness is legendary. He's constantly stumbling into compromising situations with the girls around him, usually by accident (or so he claims). This is kind of the whole joke with his character.
Despite being hung up on Haruna, he gradually develops actual feelings for Lala, an alien girl who shows up early on. The series spends a lot of time playing with whether these feelings are real or just him being confused. He definitely thinks about her even when he's around a very naked Haruna, which says something. By the end of the series he basically admits he loves both of them. Lala's cool with it since apparently once he becomes king of the universe, Earth laws don't matter anyway. She straps a jetpack to him and sends him to confess to Haruna—who dodges out of the way just like she always does.
The result? He ends up declaring his love to basically every female character except his sister, Mikan, and Haruna herself. The story implies his romantic chaos is far from over.
Content compiled by AnimeList.moe from publicly available sources.