I hope you didn't mean sth like girl meets a guy who tells her "I'll protect you forever ( meaning = till I score )", sth with school life ?
Kakan no madonna
Tsuki no shippo
Ao no Fuuin <- well, it kinda...turned out that way
Bloody Kiss
Black Bird
Hoosamguk High
Mei-chan no Shitsuji
Ultimate Venus
Lady and bodyguard
Bad Guy
Kindan no Koi wo Shiyou ekhu ekhu...very specific

oneshots:
Princess Paffy and the 40 Thieves
Pale Sacrifice from Choukyouai

I second Demon Scared, it really is worth giving it a try.

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Still the bad cop.

Try reading Limited Lovers, and check out some of the scans from Esthétique
i believe they have the anga you are looking for

wow, so many replies... arigatou

well, what I mean by protector is simply "protect, because i want to" or "protect, because i have to (like, I-have-my-secret-reasons-to-do-this type)"

But anyway, the titles you're all giving me are more or less suit my taste.

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