Liveta

Luna and Formicarium are rival factions plotting to seize a territory called Liveta. The Luna family have the upper hand in the area, and thus Victor Luna, notorious for his killing sprees, resides there as de facto ruler. Enter Yohan, a bumbling puppy-dog type who has become a Formicarium spy out of dire circumstances. When Yohan meets Victor under the guise of being his guard, he is expecting sharp edges and a fiery temper... But the first thing Victor wants to confirm about Yohan isn't his trustworthiness, but the size of what's in his pants.

(Source: Lezhin Comics)