Anything where you see the main character turn from a badass person or a hoodlum (guy) or a promiscuous bitch into some sweet person. with a touch of romance would be nice.

Bitter Virgin. Main character goes from being a popular jerk to a caring person.

Glados is a bitch. She made me kill the companion cube, the only friend I'll ever have. 😢

Chibidoro-sama=Neko-freak

Goong
Uwasa no Midori-kun
not really sure since only vol 1 was released but The Devil within

Hmm, not quite what i was searching for, I was thinking more along the lines of the main protagonist starting out as some evil a**hole or some complete jerk, but like in vol2 or some time early in the manga/anime he or she changes and hasta go thru the rest of the manga tryin to atone for sins
(kinda like Rurouni Kenshin but w.o the historical, and with more school life/romance. hopefully this isnt wayyyy too specific lol)

It's really a difficult question. Maybe Bokura ga ita or Vampire Game.
VG is probably the one (that i've read) that fit your description more, but

1. He's not the real main character, the main character is a girl. He's the antagonist.
2. It's not so clear his "conversion" 'cause he keep babbling about his revenge, but for me he's already become a good guy from the second volume.
   (It's a really good manga IMO, so I think it worth a try even if it's not exactly waht you are looking for.)

What I like in Trivial Pursuit style. Pick your category:[img]http://i379.photobucket.com/albums/oo233/Reid4891/Manga/trivia-1.jpg[/img]

Lover Discovery

Quote from blakraven66

Goong
Uwasa no Midori-kun
not really sure since only vol 1 was released but The Devil within

The Devil Within is actually 2 volumes long. I know I'm going off-topic, but I just wanted to point that out.

[url=http:////www.mangaupdates.com/showtopic.php?tid=42718][img]http://i366.photobucket.com/albums/oo105/CatzCradle64/Avis-Sigs/FunghiPower_zps2a00ba56copy_zpsfc03990e.png[/img][/url]

This might be a little off track, but I'd recommend superior if you don't mind fantasy. The main character goes from a cold killer to a more caring person (though I wouldn't exactly say completely 'good'). There is also the romance factor that you might be looking for.

I think you're so cool and can't lose you might also qualify. It's been a ahile so I might be a little off from what I remember, (someone correct me if I'm wrong) though I think the main protagonists still retain a certain amount of jerkiness at the end.

mOE KARE!
Honey x Honey Drops
Love Celeb
B-Men Kazoku
Rockin'heaven
MARS (*highly recommend this for what ur looking for)
Deep Blue

I agree, MARs for sure.

I second Mars <3

And a lot of the ones dreamit mentioned. XP

But I don't think in Love Celeb Gin stops being so much a lusty idiot... xD

Ludwig Kakumei<==sorta
Aishiteruze Baby <== was a player...

[url=http:////www.mangaupdates.com/showtopic.php?tid=42718][img]http://i366.photobucket.com/albums/oo105/CatzCradle64/Avis-Sigs/FunghiPower_zps2a00ba56copy_zpsfc03990e.png[/img][/url]