A. You can edit tags yourself. B. The going rule is "tag what you see", and since all you can see of the male in this pic is a schlong and some white pubes, it could be Locke, or it could be Setzer, or Emperor Gestahl, or whatever. Since there's no certain trait that identifies this as Locke, it doesn't get the tag. C. We go by the original names here. Final Fantasy 3 was a different game in Japan (it was one of those that came out on the NES, and it recently got a remake on the DS internationally anyway), so the final_fantasy_vi tag stays.
Locke doesn't have green or white hair. It's light brown. It's probably Setzer, this is probably reference to the game they played where they flipped a coin and if she won they'd get the airship, but if he won she'd be his.
Or I guess it could be the Emperor, but... I don't know, I guess I expect him to be more wrinkly?