Yuutousei wa Unmei no Akaiito ni Sakaraitai

Miyanari is a straight-laced model student who, one day, suddenly starts being able to see a red string connecting him to Hashiba, a delinquent in his class. "There's no way such a person would be my fated person!" Even as he repeats this to himself, it's as if the red string is playing tricks on him as he finds himself in various situations with Hashiba like getting treated by Hashiba when he got injured and getting stuck in a space alone with Hashiba, among others. As Miyanari spends more time with Hashiba, he begins to find out about Hashiba's gentle side that's different from his appearance... (Source: Frontier Works, translated)