OH SHIT!

From my extensive research notes on tentacles I shall now boldly quote... *clears throat and dramatically whips out big stack of notes*
"Green tentacles tend to be of a more friendly temper than the purple ones. While still restraining and invading their captives against their will, they tend to be much slower and more careful with their invasions than their purple counterparts, giving the victim more time to mentally prepare for what is going to happen. In addition to that, green tentacles are 3 times less likely to infuse you with anything that has a lasting effect, like eggs, impragnating fluids or mind-controlling polyps. On the other hand, purple tentacles smell much nicer and their fluids taste way less nasty when they go for oral penetration."

So yeah, purple tentales are all in all quite a bit worse than green ones. Why do you ask? :)