I think Meteor Methuselah is the only example I know with a plot like this - where one character intends to murder the other character but they end up as partners instead.
Any genre is fine, including yaoi. Thanks in advance. ^__^

Wrestle! The Under Ground only has a few chapters scanlated, but appears to be headed in that direction.

Superior, and its sequel Superior† would also fit, I think.

If you're okay with shonen ai:
Koori no Mamono no Monogatari - Demon initially wanted to kill a traveler that wandered into the cave where he was sealed. Ends up falling in love, and decides to keep him safe.

Superior From what I understand, the female lead intended to kill the main character, but falls in love, and ends up not killing him.

Inuyasha :lol: I guess this fits xD Inuyasha did originally want to kill Kagome, but then ended up liking her.

Basara I've only read a bit, but it seems to be going that way.

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Hanatsukihime

I'd say Kanata Kara matches that description. And it's a damn good manga, too. 😃

Hm, well in Ayashi no Ceres the love interest is initially employed by the protagonist's family and asked to kill her.

And it is a more minor part of the story here, but in B-Eyes the assassin protagonist is supposed to kill anyone who witnesses his actions, and the girl that he doesn't kill after she sees what he does becomes his love interest.

And there's this one I can't remember the name of that's hidden somewhere on my wishlist, where a guy is sent back in time from the future to kill this woman who is going to give birth to an evil person, but he loses his memory and falls in love with her before he remembers his purpose. At least, I think the summary was something like that.
Ed. Remembered the title. I haven't actually read it. Tenshi no Tattoo.
"This mystery guy is actually a soldier from the future who has been sent back through time to kill Misaki, for in the future she is the mother of an evil ruler. The trip through time has caused him to forget his mission until after he falls in love with Misaki."

Mugen Spiral

Corsair
Hoshiyomi no Yogensha

Quote from Illegal Goddess

I think Meteor Methuselah is the only example I know with a plot like this - where one character intends to murder the other character but they end up as partners instead.
Any genre is fine, including yaoi. Thanks in advance. ^__^

I believe this commonly happens with ninja girls.

Because ninja girls live in shadow, the only males they tend to meet outside of their tribe are assasination targets they fail to kill. Occasionally with a code of honor that turns them into companions when they fail to kill people.

Inuyasha :lol: I guess this fits xD Inuyasha did originally want to kill Kagome, but then ended up liking her.

Nobody likes Kagome.

in harems its common for at least one of the girls to start as someone who starts as an assasin, sent to kill him.

Like Sora No Otoshimono, for instance, I'm pretty sure most of the angeloids were initially sent to attack him.

Quote from red255

in harems its common for at least one of the girls to start as someone who starts as an assasin, sent to kill him.

Like Sora No Otoshimono, for instance, I'm pretty sure most of the angeloids were initially sent to attack him.

To Love-Ru with Yami is another example of this.

Have to agree with the others, I think the theme is far more common than you think. : )

superior sounds perfect, demon queen intends to kill the hero at first, but gains an interest in him and ends up as his campanion instead.

Watashi no Ookami-san - Much more light-hearted but it starts off like that. Heroine intends to vanquish the demon lord but ends up traveling with him instead. It's pretty funny.

Kurohime
She's not a character with an important role though.