No yaoi, no yuri (I have nothing against it, just personal preference), no ecchi, no hentai, no horror.

I would love more if it is Seinen or Josei!

I lurk every there and then.

I only know Mars

Isn't this routine in manga, at least in shonen manga? Guys routinely act like frightened virgins when women come on to them. I've always wondered about this. Maybe they are taught to act that way by their parents.

Easy example, Strawberry 100 Percent. That behavior helps string out the story for many volumes.

I gather that what you are seeking is a manga whose lead had a phobia regarding physical intimacy. Bitter Virgin is probably the best example of this, though it isn't a direct thing. Sekai Oni has it for the protagonist, though some of the other characters contradict that (it's enjoyable in a REALLY messed up sort of way). As someone else already mentioned, there's Mars. The Sacred Blacksmith and Berserk both have episodes of fear of physical intimacy. If you're okay with shoujo ai (that is GL without sex-scenes) there is the second story of Haru Natsu Aki Fuyu. If you are willing to try Yaoi (the type that DOES have some sex, just not often, because the plot is more important), then Ten Count is a definite possibility. For regular fear of touch, there's Fureru Ondo.