"Ku! Koro!" (short for "Gh! Just kill me!") is a phrase stemming from proud female knight characters being defeated and asking for death rather than dishonor right before being raped in that kind of rape fantasy. It's associated with Ark Royal because of her knight-like attitude. In this case, the "ro" of "koro" is the start of "Royal", as a difficult-to-translate pun on her name.