i dont prefer anyone for sheldon xD I like penny shes not this arrogant you know but i'd like penny x Leonard better cuz he really really cares for Penny. Thats why I better want sheldon alone cuz hes just not that type of loving someone xDD
Why? Because I want to see him lost and far from his comfort zone. I think it would be interessant (and hilarious) if Sheldon could fall in love. He would try to deny or fight his feelings... And he would be so disturbed!
If he was asexual, he wouldn't have said (in the first season) that Penny was attractive. He wouldn't have looked at her (and at her "soup tattoo"), when she was naked in the third season and he would have answered to Amy, when she asked him if he was jaleous or not(in the fourth season).
You know, he also said he just suppresses his feelings and his desire... (4x10) So, he's not asexual! You can watch the scene here, if you don't believe me : [link] !
Even god couldn't change Sheldon. xD I think although he was in love with a girl, he wouldn't bring flowers or listen to her... He's Sheldon Cooper and Sheldon Cooper wouldn't do that. But I think I would be funny to see him lost because he don't understand what happen to him and why he wants to... copulate (LOL).