The Dirty Way to Destroy the Goddess's Hero Vol. 1 (light novel)

Fed up with cocky heroes
always looking to save the day when all he wants is to find delicious treats for
his cute daughter, the blue demon king of the underworld calls upon a young
boy--Sotoyama Shinichi--for assistance. Once the two make a deal, the king
resumes his visit to the human world until he realizes he may have chosen the
wrong person for the job...