"No! We've hit some kind of interference... Something's wrong! We're going to crash!" - This article is a port from VVVVVV Wiki (not Space Station).
Viridian appears here on the icon for VVVVVV itself, flipped upside down.
In Outer Space
Captain Viridian (ビリジアン in color) is the captain of the D.S.S. Souleye. They are also the main character / player character of the game VVVVVV. Their most prominent ability is flipping gravity, which helps them traverse areas which would be impossible for regular human beings. They appear as a cyan stickman. At most times they are highly optimistic, but in some cutscenes and dialogue, they do doubt their ability to help their crew members.
In VVVVVV, when the D.S.S. Souleye was trapped in Dimension VVVVVV after hitting the "Ninstar Elevator Defense", Viridian and the five members of their crew were all seperated and teleported to seemingly random places in the dimension. Viridian then embarked on a perilous journey through the dimension to rescue their crew and find their ship.
The captain is named after Viridian, a color comparable to cyan. Many of the crew members are named after their color.
Captain Viridian's gender is never revealed in-game, though most custom-made levels treat the character as male. There isn't much evidence to support the belief that they are any specific gender, and while most people assume that he's male...
...you can believe whatever you want. The only information Terry Cavanagh has given about Viridian's gender is that he made it uncertain on purpose, and that Viridian is allegedly bi-gender. This implies that, in truth, whether Viridian is male or female or something else depends on your own point of view. For guidance, you may check the various VVVVVV forums. Some good places to start include here and here.
In the player level Quantum Tunnel, a terminal asks for Viridian's gender, but it still isn't revealed.
Viridian is a unlockable character in Super Meat Boy.