Cloud Strife, AM (AVALANCHE Member) He doesn't say much and appears detached from the world around him most of the time.
Cloud is very somber and dark, tormented by his past, which includes the deaths of two of his friends, Aerith and Zack, as such he appears quite detached and emotionally unavailable at first, making it hard to approach him for most people. And when he suddenly contracted the terminal and incurable Geostigma, which added to his feelings of helplessness, Cloud decided to distance himself from his friends and live alone trying to keep his affliction secret and seek forgiveness so that he might find a cure. Something he's not quite sure they have forgiven him for.
Cloud is not very talkative and even a little stand offish at time it's easier to end up on his bad side then his good one. But, once on his good side it's easy to see he cares for his friends, even if he has a little trouble showing it at time. He can even become joking and teasing if he's close enough to someone to feel comfortable doing it.* Cloud will fight his hardest for what he believes him, and Prides himself on getting the jobs he takes, done.
*For all those rolling your eyes thinking "Great, another OOC Cloud". Read up on it, Cloud DOES joke around with his friends in the game story line, even so far as to make Aerith agree to a date with him to save her. "Aerith: Then, get me out of here. Take me home. / Cloud: OK, I'll do it... but it'll cost you. / Aerith: Well then, let's see...... How about if I go out with you once? / [Cloud makes an affirmative nod.] Square Co.. Final Fantasy VII. (SCE America). PlayStation. (1997-09-07)." Just because he was a real loner and emo in Advent Children doesn't mean he's always such. That just happened to be ONE PEEK at Cloud in the FF World. Kthnxbai.
Clouds' past is a burden upon his shoulders that he appears to have no plans on taking off. He simply lives with his guilt and pain everyday, sometimes using it to fuel himself into doing better and working harder, as if what he does now will sometime fix the past.
Being a loner he often is seen traveling around without anyone with him, and often doesn't talk much to even people he knows. Even going so far as to never answer his phone and only listen to his messages without often calling a person back.
From being a part of SOLIDER, Cloud is infused with Mako, those who have had exposure to Mako have a glow in their eyes, called "Mako Eyes." Some other known abilities also occur due to the Mako.