Responses
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This is the first one I thought of but I think there's another one out there where they also kiss to fight. I'll see if I can find that one.
https://www.mangago.zone/read-manga/datte_maou_sama_wa_kare_ga_kirai/
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https://www.mangago.zone/read-manga/the_chronicles_of_pulau/
This one popped into my head but I don't think it's what you're looking for
So this may sound extremely vague but it's literally all I remember. And it's been in my memories for so long but can't find it. All I remember is that it's sort of like 2 families that have some sort of power. And it's like fallen to 2 guys who have to win against the oth and the only way to win is in a kiss or something. And they constantly kiss and fight. They're not gay in the beginning but like always they do at the end lol