help in a manga

hi (^_^)/
im trying to find a manga that alogn time ago i started reading it but i didnt finished
i dont remenber much of the story ,just certain bits ,also dont remenber any names
theres this main charather that he is both genders from the waist up he is a boy and from the waist down he is a girl,or is the oposit,he wants to be seen has a guy
theres a another guy interested in him and tries to flirt with him at times,but i think the main character gets annoyid at the guy
,the main charather has a crush on this girl who dosnt know he has both genders,i think that the girl some how finds out cause i remenber one time the main character entered into her room by the windon and they spend the night together (including sexual)
also the main character has this moments where its like he is fighting with himself in dreams where two versions of him a girl and a boy try to fight ,the girl trying to put the boy side in danger
thats all i remenber,does anyone know what manga it is?