Partial Derivative

It's a yellow algebra alien with lighter limbs; its shape resembles the number 6 but upside down (i.e., turned the other way), although it's actually a cursive "d". It wears glasses with funny eyes (i.e., one facing up and the other down) that it made itself for fun.

He usually gets along well with everyone, but his best friend will always be "Sigma" since Sigma is a pretty cool and admirable symbol for him. Psi is also a close friend, like Sigma, and his friend Nabla, with whom he is openly in love, although he doesn't tell Nabla, only his trusted friends.

He is friendly, subtle, and sensible; he has great inspiration and loves mechanics and creating things, from machinery to simpler things like his scooter. He is known for creating various things.