TBH i also didn't understand that sentence at first because the 'X' just blew my mind and '狩場の共演' is also weird(even a japanese asked what does that mean in 5ch), not understanding the sentence to translate it, it's difficult too. The reason why he got 'Onigari' is probably because of '十鬼X狩場' if you delete the X and the other 2 kanjis and the X you get '鬼狩' Onigari, that's the only reason to why i can think that he got Onigari.