A man accused of making hostile threats in connection with a popular manga series admitted full guilt in court Thursday, vowing to embrace any penalties without appealing and pushing for severe punishment, suggesting he wants to kill himself.

Hirofumi Watanabe was arrested last December for masterminding hateful campaigns against the popular comic book "Kuroko no Basuke" ("Kuroko's Basketball"), authored by Tadatoshi Fujimaki. Threats were repeatedly sent to organizers nationwide that were planning events based on the manga.

The 36-year-old temp worker also placed a container filled with hydrogen sulfide on the premises of Sophia University in Tokyo in October 2012 along with a letter revealing his grudge against Fujimaki, who graduated from the Catholic university.