 If you liked
Kageno datte Seishun Shitai
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 ...then you might like
Boku no Orion
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Both are shoujo mangas about the relationship of a popular guy and the unpopular high school girl with clear self-esteem issues.
KdSS is heavier on the comedy side while BnO has a lot more introspection.
KdSS is the story told from the girl's side while in BnO the narrator is the guy, this makes KdSS male MC a comically perfect guy while in BnO the male MC has real flaws.
If you like KdSS and are looking for something slightly more serious go with BnO. If you like BnO and you're looking for something a bit more lighthearted, go with KdSS.