Luke Notos Greyrat

Luke was born into the Notos Greyrat family as an Asura Kingdom high noble. He was tasked at a very young age of being the Guardian Knight to second princess Ariel Anemoi Asura alongside Derrick Redbat. He is very fervent in his duties as a guardian despite his frivolous attitude toward girls and his mediocre skills.

(Source: Mushoku Tensei Wiki)