Butterfly Dream Pill
The Butterfly Dream Pill (胡蝶夢丸 Kochoumugan) is a drug created by Eirin Yagokoro, a red pill which gives the user pleasant dreams of flying around as a butterfly. Ancient versions of the drug could risk the user being trapped in the Dream World; the one sold by Eirin is designed to reduce the risk of side-effects. A black version, Butterfly Dream Pill - Nightmare Type (胡蝶夢丸ナイトメアタイプ), is also available, which gives the user nightmares.
Alice Margatroid is a known user of the red pills. Eirin uses the black pills in her spell card Medicine Sign "Butterfly Dream Pill - Nightmare Type".