The Cursed Sword Master's Harem Life: By the Sword, for the Sword Vol. 4 -

Sojiro's second katana, Sakura, has been stolen by Frey and taken into the depths of a dangerous tower! Just when he thinks he's caught up to the thief and former ally, he encounters Dragomantis, an incredibly dangerous monster and boss of the floor. With Sakura missing and his beloved sword Hotarumaru gravely injured, how can Sojiro survive this encounter?!