2gae4u

I'm looking for a manga i lost. (I remember it being b/w so I assume it is a manga)
I don't really know if I remember this correctly so pls bear w meee
The fl was an elf/witch(?) she lives in the forest, she's the only one living in the forest. Since elves live longer I think she was kinda like isolated cuz she was all alone there in the forest. So then the mc (ml) appears to be a child he got there out of nowhere and then fl elf took care of him and so on then he became grown up (?)
Pls it wasn't any wierd manga I swear it was a masterpiece (I hope my memory is right). Pls plsss help me find itttt
I remember later on it was revealed, initially in the past they already met as both adults and were actually lovers but he died because he was a human. So the ml actually kept reincarnating and always found his way back to the forest every time.
I read it almost 3 years ago I really wanna see it again. The title was also in japanese which made it harder for me to remember