Emiya Shirou

The protagonist of Fate/stay night… but that should go without saying.
He is a diligent, hardworking man, who loves things like cooking, cleaning, and sewing. Though he always denies it, saying that he simply has no choice but to do all those things himself, that’s an obvious lie. He’s destined to become a housekeeper.
His inborn butler spirit will reveal itself after Rin’s true ending, when he gets a part-time job working in the mansion of Rin’s rival. Wait, what?
Also, though he’ll remain a failure of a magus to the bitter end, he’ll achieve great things as a spellcaster.

Fate/side material: Fate Encyclopedia

A half-baked magus’ apprentice who was taught magecraft by his late adoptive father. He righteously comes to the rescue of the idiots who have forgotten their wallets. In the animated movie, his manliness is something to behold no matter how much flak comes his way.

HibiChika Complete Capture Book: Mahou Tsukai no Hako Small Encylopedia

Shirou is one of the few survivors of the Fuyuki Great Fire. He was narrowly saved by Kiritsugu. After losing everything in the Fourth Holy Grail War, Shirou’s existence becomes Kiritsugu’s last hope. Shirou lost his relatives in the fire, so Kiritsugu takes him in as his adopted son. They move in and restore the Japanese manor in Miyama Town that was formerly used as Irisviel’s secret hideout. They spend five years together in this house before Kiritsugu breathed his last. Shirou calls Kiritsugu “old man” despite him not even being 40 yet. Shirou absolutely adores Kiritsugu. Shirou is influenced by Kiritsugu, and comes to possess what can be only called an excessive sense of self-sacrifice and justice. Kiritsugu’s only regret is how Shirou took after him in this way. Shirou admires Kiritsugu and inherits the ideal of becoming a Hero of Justice. He follows that path to the stone, which becomes especially apparent after the breakout of the Fifth Holy Grail War.

Fate/Zero Animation Guide II: Glossary of the holy grail war II