Vent (CAV-4)

Vent is a bit of an anomaly. Registered in Eggman's databases as "Test Model NM-155", but known better to his friends (and enemies) as Vent, he's some sort of weird android that acts way too lifelike to be an ordinary machine. He also has the ability to copy the data of anybody and any weapon he sees to integrate it and upgrade himself, which makes him a formidable foe... although he usually uses it to goof off and bother his roommate, Double.

Vent has no memory of why he was built or what his purpose is, asides from the fact that he "woke up" with a feeling that something was deeply wrong with his existence. After being found and repaired by Double, he's dedicated his life to being a fun nuisance while also being a hero on the side. Hey, if he can't remember anything, he might as well pick a purpose for himself, right? Besides, being a hero and saving the day is more fun than being an unstoppable weapon of mass destruction.

Most of his interactions with people are him being lighthearted and teasing them, which with Double often leads to various scuffles that Vent usually loses. He also takes weird multiverse stuff in stride, seeing as he's best buds with Copy as well. His closest friend outside of the Dallases is Aile; their shared backstory plays into it, but really Vent just worries about him and wants to try and help him have a good time.

He met Sonic when she kicked him in the face.