Summary: S-Rank adventurer and second-generation sword saint, Ryunoa Styler, is reunited with his childhood friend, Aine, who has been reduced to slavery. Ryunoa purchases Aine in order to save her, however, she\'s been given a cursed collar that causes the wearer to go into \'heat\' once a day... Ryunoa\'s battle to find a way to remove the collar starts now!