The Strongest Sage with the Weakest Crest 20 (manga)

Despite having previously refused a noble title and land, Matthias eventually relents when the king of Eis gives him an attractive offer. As the new lord of Boseil, Matty is inundated with political marriage proposals! To escape troublesome political affairs, Matty and his friends head out to explore the dungeon near Boseil, but it seems the real trouble is in the dungeon!