Despite coming off as bitter and grumpy through his speech, he has a gentle, tender, and modest nature. In his childhood, Diluc had a lighthearted and happy nature, rather to the contrary of him now. Diluc holds a bit of resentment towards the Knights of Favonius due to the incident with Inspector Eroch. He claims that the Knights take too long to get the job done, although he still appreciates those who put the effort in.

Despite being an owner of a winery and tavern, he hates alcohol.