Artist's commentary
Touhou 4-Panel Strips #1506 Fidgety
Osa-Keine just automatically grips them into rice balls!
[Survey: Which rice ball flavor do you prefer?]
• Sea chicken with mayo
• Mentaiko
• Salmon
• Sekihan steamed glutinous rice
• Salt
I.e., tuna (a.k.a. "chicken of the sea ") with mayonnaise. The first choice is literally "sea chicken mayo" in katakana.