- Her first name, Raiko, (らいこ 雷鼓) means Thunder Drum. Her last name, Horikawa (堀川) means "Canal".
- Her unique danmaku is a taiko drum.
- Raiko, along with Kaguya Houraisan, Nue Houjuu, Kogasa Tatara etc, are one of the few characters in Touhou who have no kind of headgear.
- Raiko is one of the 8 musicians. The others are: Prismriver Sisters, Mystia Lorelei, Kyouko Kasodani, and the Tsukumo sisters Benben and Yatsuhashi.
Ad blocker interference detected!
Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers
Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.