My Monster Secret, known in Japan as Actually, I Am... (実は私は, Jitsu wa Watashi wa), is a Japanese manga series written and illustrated by Eiji Masuda. It was serialized in Akita Shoten's shōnen manga magazine Weekly Shōnen Champion from January 31, 2013, to February 16, 2017. Akita Shoten collected the series in 22 tankōbon volumes.

An anime television series adaptation ran from July to September 2015. AnimeLab has secured streaming rights in Australia and New Zealand.

Seven Seas Entertainment acquired the rights to translate and distribute the manga for North America, with the first volume being released in January 2016.

Asahi Kuromine, a normal high school student who supposedly cannot keep a secret, finds his demeanor quickly challenged when he spots his classmate and crush, Youko Shiragami, unfurling a large pair of wings from her back when he tries to propose. He learns Youko is a vampire, and she is only able to attend a normal school on one condition: no one must discover her true identity. This secret becomes difficult to maintain, as Youko herself is an airhead and Asahi's childhood friend Mikan keeps bullying the two of them. Love is blooming between Asahi and Youko but things are not very easy. Later on, Asahi discovers more girls in his school with secrets of their own: a tiny alien who rides a human-sized exoskeleton of herself, a werewolf capable of switching gender at any depiction of a moon, a thousand-year-old demon who secretly runs the school, and more who not only pose a challenge as Asahi tries to maintain Youko's secret, but also secretly like Asahi and despise the idea of Asahi and Youko being a couple, thus trying to separate them.