Looking for a SHOUJO, JOSEI OR BL manga in which the main couple begins as a rebound, replacement or pretend relationship... But they slowly become a real couple.

Sample scenarios: A is still in love with an ex and only goes out with B as a rebound, but then begins to love B back for real. Or A is an undercover spy/enemy only pretending to fall in love with B, but then falls for real. Or A is in love with B's sibling/twin/friend who cannot accept them and so goes out with B as a replacement, but A's feelings slowly become real and B stops being just a replacement.

Like in Koishi Tagari no Blue, the guy asks the girl to be his "pretend" girlfriend but he seriously falls for her.

Or Zettai Heiwa Daisakusen, where the couple only pretends to be in love for political reasons, but their pretense eventually becomes real.

Or Junjou Romantica, where Hiro and Nowaki begin as a rebound relationship and eventually turn into a real one.

Or Lizard Prince, where the guy is only a surrogate for another guy who the girl is supposed to marry, but he wins the girl's heart anyway.

Or Empty Heart, where the protagonist has to be a replacement for his brother in order to get into his love interest's bed, but eventually, said interest loves him back for who he is, not for his similarities to his brother.

Any more like these?

Thanks!

Zig Zag Don -- This pretty much has what you're looking for, I think?
Obaka-chan, Koigatariki -- I feel like it's a rebound relationship... but I'm not sure how it'll develop since it started in only the latest scanlated chapter XD
S+ -- This doesn't actually depict them getting together at the end, but it's kinda got what you want
Koizora -- Eventually she gets a better boyfriend...
Stardust Wink -- Maybe, though not really :/
Yoru Cafe -- Perhaps?
Kiss & Never Cry -- Possibly. From what I saw in the raws XD

The second story in Clover (OTSU Hiyori) and the third in Mermaid Line.

http://www.mangaupdates.com/series.html?category=Pretend+Lovers

Love Graduation
Narabuna Kiken!!
Peppermint

♪MONSTARR~ will eat all your cookies and steal your bishies~♪ Φ_Φ

Renai Kyoutei Nukegake Nashi!

Hapi Mari kinda fits in the "pretend" category. Their marriage is more of a mutually beneficial agreement than one based on love. The part that fits is that they get married and pretend to be happily so in order to dupe the groom's grandfather.

Feed your head.

Hadashi de Bara wo Fume

世界のどこかに必ず
キミの居場所がある筈

Gakuen Ouji !

Definitely fits your outline.

Thank you all! Pls keep reccing!