Hybrids may not be allowed, but picture this: the (fraternal) twins of a simpire and an alien teaming together to become an inseparable pair of evil genius masterminds. Just imagine the power they could hold over the simiverse! Every sim in the world would be ripe for the taking, the power fizzing right at their fingertips - one drains you, the other reads your mind and reveals all of your deepest, darkest secrets. They could take down nations, the blood thirst and powers of seduction of the heartthrob simpire working in perfect tandem with that of the extraterrestrial abilities of their little green twin in the sky.
Or perhaps these rambunctious scamps could take the high road, using their powers of compelling and MIB-like memory wiping to solve the unsolvable, become the most praised detectives in the land just because it is the right thing to do.
...Although, hybrids do seem very tempting. Mess up your first date? Did you snort out popcorn whilst watching the movie, or yawn and stretch a bit too prominently just as that coincidentally timed romantic scene came on? No problemo! Just perform one simple memory wipe, and all is well... That is, as long as you don't mind getting to know your little lovebird *yet again*. How many times have you screwed up this date? 500?! Okay, okay. Forget that. You're a vampire (cough, cough half alien) heart throb. It's prime time to use your powers of seduction, dude. Compel the heck out of that woman, she is leaving this date in a flirty mood or you are retiring to your coffin to sulk and brood for the remainder of your - immortal - lifetime. Or you could always seduce her the old-fashioned way, but what's the fun in that?