Zach Sutton is the bassist/keyboardist for Minnesotan band Hippo Campus., born on February 19, 1996.

In December 2022, Zach released his debut solo project under the moniker Mono Moon. The name is based on a nickname given to him by a friend, which was later adapted to “moon boy” in Hippo Campus' 2017 track “Baseball”.

Within the band, he is sometimes known as “Espo”, which also serves as his social media handle (espocampus). Band mate Nathan Stocker explained this nickname:

Zach lived in Finland for a while as a kid and Espo(o) is a city in Finland, so that’s why we call him Espo.

In the band’s second LP, Zach was featured as a primary lyricist for the first time, in “Anxious” and “Doubt”.