Yobidasareta Satsurikusha, summoned slaughterer.

Touno Hifumi was summoned to another world, to be a Hero for a kingdom. Unbeknownst to the summoners, he's a kill-happy person who restrained his killer instincts with martial arts. Upon arrival he slaughter various knights and the mastermind of the event, the King. Unwilling to oppose this strong killer, the Princess let him go free. Thus start the fun life of travelling the world, unrestraintly killing any who attempt to kill him. But first, lets purchase a pair of female slaves. Source: MU