Hiroko has a pale complexion and slanted eyes. She has long blonde hair.
Her normal attire is a purple school sailor uniform, while her shinobi outfit consists of a black form fit top accented in white and purple with the bottom portion flowing behind her lower torso and appearing severely ripped up. She wears black wrist protectors, black stockings, and a black thong. On her head is a black hat with gold eyes and devil horns, along with two tiny arms attached to a small red boxing gloved hand.
She seems to be a typical delinquent, though she is willing to do odd jobs for food or cash. She seems to have a few "gyaru" traits, similar to Shiki.
BackgroundDuring the NINJA†RIDERS event, she and her friends appeared in their school uniforms as bosses, though they may have been under the influence of Reki who was the final boss of the event.
She and Reika (but not Mayumi) next appeared for the Yin Yang Shinobi Squadron 3 event, where they wore what would later be known as their shinobi outfits. However, this event was a Hero Show that Hisui was helping a friend with, and Reika and Hiroko were being paid to act as the villains, so at the time these costumes were just the villain suits for their production (hence why they say "Villain" on them), but later on these suits seemed to be treated as their actual shinobi forms.
Reika and Hiroko would later appear again to crash Mirai's Birthday Festival, wearing their villain suits and possibly under the influece of Reki again.
Her eyes are shown to be red during the times when she may be under the influence of Reki.
Hiroko was a non-playable boss that appeared for events in Senran Kagura: New Wave.
- Hiroko's name can mean "Fathom".
- Her Shinobi Transformation features the kanji for "Evil" and "Party" on her chest, which when taken together mean "Villain." There is also artwork where she has painted the kanji across her bare chest.