Comments of chapter undefined of An Extra's Gambit

Abnormally:Unfortunately, he can't use 'that' Mana to cast spells as it requires the mana to travel through his body to 'conjure a spell' and since he does have a terminal illness, his body is unable to support this mana 'journey' through his body ( you can think of it as if his meridians responsible for storing and moving mana are ripped apart ) So apart from casting spells he can try to interact with mana outside his body, but again, he has no experience nor clue how to do it as he was always Manaless.