Fate/stay night, Kurokami The Animation Recommendations
These are both fantasy anime about a man who has a contract with a rather skilled girl that comes from nowhere. Moreover, the guy seems really useless at the beginning but will begin to fight along with her.
In both anime, the main character makes a contract with another character. You also get the same vibe from watching both.
Both anime are about an average and boring guy who suddenly meets a strong and cute girl who has super powers. The two make a contract together and (initially) have a master-servant relationship, where the girl fights, and the guy is basically useless.
Also, in both anime the main guy is an orphan, and has a childhood friend who is clearly in love with him (Sakura in FSN, Akane in Kurokami).
Both are shounen anime which have fantasy, magic, action, and drama.
Kurokami is more fast-paced and overall better than FSN, though.
In both anime we have a more or less normal male protagonist who makes a contract with powerful supernatural being (or more precisely a girl). As time passes both are trown into a lot of fights and they learn to how to effectively support their supernatural partners (althought they are always supporters and they practically cannot fight on their own).
The story is about a man who make contract with unknown woman because he was in the verge of death,after he was been saved by the woman he is find out about doppel liner system bit by bit then he find out that he was root.although he was not root he still fight to change his destiny.
They both surrend teams of tweo people working together for a cause.
They both have's similar aspect's like FSN...In both anime's there are mark's on the hand's of the fighter and in both anime's just 1 person fights and the other one give's commands.Very similar stories
These two anime have a similar air to them. Shirou can be compared to Kurokami's male protagonist Keita, as they both enter a world of fighting with beings far greater than themselves. In F/SN we have servants while in Kurokami, we have Motutsumitama. If you like F/SN, you'll definitely enjoy Kurokami
although the ambition of the protagonist in each anime is different but both protagonist character is rather similar very determined despite their lack of power and willing to sacrifice itself to save the people. theres also about forming contract however in kurokami is not a contract between ancient champions but more with a powerful race known as motosumitama.