Mahou Senshi Louie

On the great continent of Alecrast exists the Kingdom of Swords, Ohfun. Louie, an unorthodox magician with hulking muscles from the Magician's Guild, spent his days surrounded by women, booze, and brawls. But on the night of celebrating his promotion to Sorcerer with his colleague, Aila, he comes across a scuffle between knight apprentices and 3 female adventurers: Merrill, Genie, and Melissa. Unable to resist the urge, Louie jumps into the fray....

(Source: Kadokawa, translated)