I'm looking for a manga where the main characters are experiencing forbidden love since one is an angel and one is a demon.

Also I know this wasn't in the title but how about a manga where two opposing kingdoms prince and princess fall in love??

Answers will be really appreciated! Im on thanksgiving break so MANGA TIME

Superior the demon lord falls inlove with the Paladin whose supposed to kill her, and since I´m at it theres also Nisekoi, the two of them are from opposing yakuza families, but they are forced to be a couple.

For the prince-princess thing try Zettai Heiwa Daisakusen... 🙂

There's nothing to see here. Proceed with what you were doing or throw rainbows at random pedestrians.

I'm reading nisekoi and I read zettai heiwa daisakusen 😃

Some other manga came to my mind, although they are not exactly what you wanted:
Adarushan no Hanayome
Hyakunen Renbo prince x witch, while witches are very prejudged being evil in his kingdom

There's nothing to see here. Proceed with what you were doing or throw rainbows at random pedestrians.

I can't think of anything exactly as you described, but you might want to give these a look:
The Demon Within - angels and demons, but a twist on which is which, not really forbidden love - in fact, the girl is supposed to choose one as a husband.
Angel Sanctuary - filled with angels and demons, not sure if there is forbidden love between them, but there's some pretty wild stuff going on.
Akuma na Eros - Satan and an angel are competitors for the girl. As reviewer MightyMaeve describes it, it is "simplistic and ridiculous, but a page-turner."
Earthian - there is forbidden romance between angels and humans, but also between the two male main characters who are both angels.

For your other request, Basara, and Reimei no Arcana looks like it would fit.

Ao no Fuuin
Angel at War
Masca
Seimaden

I'm on Thanksgiving break too and definitely manga time. I second Basara and Superior.

Oh wow thanks!!! Sry if I wasn't specific.. hm but for the princess / prince thing I'm looking for something where they choose each other despite their kingdoms wishes. Not by an "alliance" . So each side completely hates each other 😀

Angel/demon/human relationships:

The devil ororon
demon flower
(second angel at war)

Families forbid them to be together/Opposite sides:

Snow drop
Basara
Akagami no shirayukihime (i think, can't entirely remember the problems, might have been a class issue instead...)

Mermaid/human:

Evyione

Separated by stations in life:

Shisei (YOKOBABA Ryo)
Emma

Princess/Prince:
Bus Hashiru ~ it's a collection of stories, but the... I think last story is what you're looking for. I'm not sure if they're royalty, but the two main characters are from two opposing lands that war against each other. It's absolutely beautiful! It's colored, too.

Angel/Demon:
A Fairytale for the Demon Lord ~ sort of? The leading female is angelic and has wings and there is a demon lord as the title suggests. It's a very beautiful but gory webcomic, full-colored. The plot is... Complicated.

I am vindicated!
I am selfish;
I am wrong!
I am right,
I swear I'm right.
Swear I knew it all along
And I am flawed!
But I am cleaning up so well
I am seeing in me now
The things you swore
You saw yourself...

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