Rensea's manga / #Orphan(1)

The Irregular of the Royal Academy of Magic

Ongoing | Kankitsu yusura,Nagatsuki fumi | 2019 released

Seriously good! An orphan commoner from the slums who can use magic is taken in by a man whilst he is at deaths door. The man gives him a choice to for on the streets like a dog or learn to kill, this is how the kid became an asassin. He is then told to enlist at the royal academy and pass 10 years later despite being a commoner.