Keikenchi Chochiku de Nonbiri Shōshinryokō ~Yūsha to Koibito ni Tsuihōsareta Senshi no Mujikaku Zamaa~ (Associated Names)

After losing his girlfriend to a brave hero, Toru is expelled from his S-Rank party. With a feeling of sadness and pain in his heart, he defeats a demon he meets outside the city, and his ability [to save experience] is broken! Toru becomes level 300 in the blink of an eye! With this power…