Elf Dorei to Kizuku Dungeon Harem: Isekai de Netotte Nakama wo Fuyashimasu

Synopsis:

Mars, a boy reincarnated into another world, sets out on a journey with Lilia, an elf slave. His ultimate goal is to conquer the world’s greatest dungeon and obtain a legendary "forbidden magic book" that holds powers beyond imagination. However, his constant intimate relationship with Lilia often ends up slowing down their progress.