Astrawberry(2003)

Astrawberry

A guy named Betty, who happens to be an alien, comes to earth to clone the perfect human slave and sell them in space to make a fortune. But the sample of a girl he used didn't work out as well as he planed. From her DNA, two clones with completely different personalities were created. A rude, sexy, big breasted blond, who calls herself Vanilla and loves Betty. And a short, sensible, worry-wort boy who is called Chocolate.

Now, he plans to stalk the human girl in order to see what went wrong. But since he's an alien and doesn't understand the ways of humans, things get complicated and he finds out that he might have feelings for this human girl...

(Source: LuffyNoTomo)