name: Emiya Kiritsuguage: deceased at the age of about 40
nationality: Japanese
profession: unknown, probably just a magician under the Einzbern.
family: Shirou (adopted son).
likes: emotions, honesty, helping people.
dislikes: war, unworth treatments.
magic powers: unknown, he was a Master of course but his weapon of choice were guns, so it's kinda impossible stating his magic abilities
servant: Saber.
personality: we don't know very much about Kiritsugu, except for the fact that he was a cool and calm person, someone who was trying to suppress his emotion to fulfill his duties, someone who was trying to give a meaning to his life by accomplishing his personal mission, but after the ending of the Grail War he couldn't find anymore a meaning to carry on. He was somehow carried by life itself, until he found a new motivation, someone to love. We have different opionions about him, different points of view.
Shirou thinks he's an heroe, someone who was ready to act in order to protect people. This is partially true. Kiritsugu was lead by his own conscience. He wasn't willing to become someone to take as a model, he wanted to destroy a system that was bad. He was acting in that way because he wanted to.
Saber considers him as someone moved only by interest, someone who could show a particular cruel side if stopped by people or circumstances. This is also true since Kiritsugu was also moved by desperation, and people in his conditions can do anything to carry on.
Kiritsugu can be definetly considered as a person with a large emotional potential but with a few chances to develop it.
spoilers warning !!!
personal story: Kiritsugu was one of the followers of the Einzbern since his youth. We don't really know if he was a magician or if he was just employed by them, though he was loyal till a certain point. He wasn't someone really ambitious and his right
nature was a big obstacle for his conscience to get through the Holy War without doing anythign to stop it.
He was understanding that game was something really dangerous, a vain dream of greatness which was only bringing misfortune. His experience led him to
fight against that system, withouth thinking twice about eventual obstacles. This is the reason why Saber disliked him, since he was ready to do anything to get to his aim, also killing people if it was needed.
She couldn't understand neither his personality nor his real motivations.
He managed to get Saber as a servant through Avalon (promising her he would give the sheat back to her if they would win the war) and using a compulsary command spell he was able to oblidge her to destroy the artifact itself and ending the war without a real winner. He survived but his body was tainted by the evil content of the Grail and he started to develop a sort of unknown illness that was slowly killing him.
After the decisive battle he found a wounded child in his way back and he decided to take care of him, realizing that young life could give him a new one as well.
He decided not to introduce Shirou to magic since he wasn't really thinking too high of his skills and mainly because he didn't want him to experience his same sufferences.
I think he passed away happilly although his happiness could only last a few years.