any manga where the guy falls really hard in love with the girl, but the girl is unaffected by it, I hate when the girls fall first and they make fools of themselves crying over the guy and falling all over themselves if he looks her way, I would like to see a guy making a fool of himself, lol- it can also be shounen-ai, yaoi- but the seme has to be the one who falls hard and then unaffected uke....

Kimi no Sei

[img]http://img91.imageshack.us/img91/120/zzzkq5.jpg[/img]

I love [color=red]vampires[/color].

Cinderella Fella
The Prince's Cactus
Reimei no Arcana--sort of, he certainly acts like he is in love and the girl definetly unaffected
Stroke Material--playboy falls hard for supercool smart beautiful girl who doesn't show her emotions easily even after she falls in love.

Angel Beats--best anime of the 2010 spring season

[/m]Skip Beat[m] = Kyoko is totally oblivious even though everyone (well, lots of people) can see how much he loves her. 😃

Oblivious isn't the same as unaffected.....but yeah, it's gonna be a long time before her condition is anything like as serious as his. So, yeah, Skip Beat!

They say it's the thought that counts, but then they tell you, "The road to hell is paved with good intentions......"

Will no one scanlate Takahashi Miyuki?! T_T

Tamago no Kimi!

Tenshi na Konamaiki ought to fit.

Moe Kare!!

Ahiru no Oujisama

Suki-tte Ii na yo
Private Prince
Let's Lagoon
Akagami no Shirayukihime
Ipaasha
Kurohime
Sekitou Elergy
Mousou Shoujo Otakukei
Lock On!

To some extent
Akatoki Hoshi Residence
Barajou no Kiss
Zettai Heiwa Daisakusen
Kaichou wa Maid-sama!
Eensy-Weensy Monster
Eikaiwa School Wars
Zippy Ziggy
Sun-ken Rock

Almost?
Hoshi no Samidare
Hajimete no Aku

Also, if you don't mind shounen, maybe if you genre search shounen + romance - harem perhaps a good portion of them will be boy chases girl. At least I think a larger percentage than shoujo.