A brief description of the manga Until the Chore Granting Sorcerer Realized That He Is At His Strongest:
Wimme Strauss is a spellcaster who specializes in supporting allies. However, when he defeats a boss, he is kicked out of the group. Wimme  is at a loss, but his childhood friend (and part-time stalker) Heidemarie finds him and recruits him into the largest group, Wings of the Dragon. He claims his achievement was a fluke, but it’s only a matter of time before those around him realize what he’s truly capable of.