SHIJŌ SAIKYŌ NO MAHŌ KENSHI, F-RANK BŌKENSHA NI TENSEI SURU: KENSEI TO MATEI, 2-TSU NO ZENSE OMOTTA OTOKO NO EIYŪTAN

Proper Japanese Title: 史上最強の魔法剣士、Fランク冒険者に転生する ~剣聖と魔帝、2つの前世を持った男の英雄譚~ Originally serialized in Dash X Comic. — Description from Comic Vine community (comicvine.gamespot.com · https://comicvine.gamespot.com/shijo-saikyo-no-maho-kenshi-f-rank-bokensha-ni-ten/4050-139383/).