All I remember, is there was this lady/girl who was in her room when she discovered this little colorful guy. Later on they discovered more of these guys. The only other one I remember would be a red guy that was angry and used explosives
I'm pretty sure they were aliens of some sort and I would say they fought big aliens (more of the stereotypes of monsters) and they all protected the girl. I do remember one of the little people were pink and they made people feel love towards her.
Is this "Keroro Gunsou"? From Wikipedia:
The story follows the attempts of a platoon of frog-like alien invaders to conquer Earth. Sergeant Keroro, the titular character, is the leader of the platoon, but is at the mercy of a human family of three after being captured by them. Keroro is forced to do meaningless chores and errands for the family after his army abandons his platoon on Earth.
The red hot-headed alien you talked about should be Giroro, which happens to be looking grumpy/angry and uses firearms.
