Urenokori no Dorei Elf wo Hirotta no de, Musume ni suru Koto ni shita

A magician named Weiss lives as he pleases in Zenith, a town filled with scoundrels, where he comes across an elf girl being sold as a slave. Weiss realizes that this girl dressed in ragged clothing is a high elf, a rare species that was supposed to have gone extinct, so he buys her and decides to raise her as his "daughter." This is a warm and fluffy fantasy featuring the rookie dad Weiss and his cute little elf girl(Source: Young Champion)