i think the art style is like clannad, this manga is old and already completed, i think below 2010 year or around 2003-2007

it was not a manga called love allergen , it has different story

basically a girl who born from the power of sakura tree

she basically a paradox being, was'nt human and a being that created by a sakura tree who has supernatural power

basically the girl and the other girl(who seems mc childhood friend) was rival and competing to get mc love(it was love triangle)

the ending is kinda sad i think but i forgot about it and heard it has sequel

so i want to read it

sorry for the trouble guys, i got really curious about this manga and remembered about it when watching sakura tree at youtube haha

thanks

I know exactly what manga you are talking about! Ugh, I can't remember it but I read it a few months ago. :/

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Nulla in mundo pax sincera
"Always go too far, because that's where you'll find the truth." - Albert Camus

I haven't read it so I might be wrong, but I think it might be Da Capo http://www.mangaupdates.com/series.html?id=2670.

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"You forget, I am not human. I am merely a weapon." - KOS-MOS