The Loser In The Daytime Is The Ruler Of The Night?!

After Luke’s boring life ended because of an unexpected accident, he reincarnated and became a labyrinth explorer. However, he couldn’t advance beyond E-rank, despite being an explorer for 15 years. Furthermore, the guild has a rule that mandates explorers to retire if they do not reach D-rank by the age of 30. Since there was only a month left until Luke turned 30, impatience drove him to accidentally trigger a warp trap he wouldn’t normally trigger. In the unfamiliar room he found himself in, he came face-to-face with a woman of peerless beauty. Then, shocking words came out of the woman’s mouth, “My brethren…A vampire won’t get stronger by slaying monsters. We only gain strength by f...