魔入りました！入間くん カルエゴ外伝 (Mairimashita! Iruma-Kun Karuego Gaiden lit: "Enrolled Demon Iruma! Kalego Side Story"?) is a two-part manga written and illustrated by Osamu Nishi. The Gaiden depicts Kalego's school life and first meeting with Opera.
It should be noted that the Gaiden is complete with 7 chapters.