Set in 2009, Cibele explores how relationships are formed on the internet a few years into the age of social media. A semi-autobiographical game, the player sees a love story played out on a fictional mmo called Valtameri through the eyes of college freshman Nina. She meets Blake and throughout three acts their budding relationship blossoms into something neither of the two have experienced before.
Each act starts with the option to explore Nina’s desktop, where the player can find messages and chat logs with Nina's friends, poetry for her college classes as well of pictures of her and later ones exchanged with Blake. However, the majority of Cibele takes place in Valtameri, a fictional MMO of a dungeon crawler type nature, where the player takes the role of the titular Cibele.
Gameplay in Valtameri consists of clicking on enemies to defeat them along with Blakes character; Ichi. Each of the three acts has a unique boss character: Akka, Sampsa, and the fearsome Kuu. Once the act boss is slain the act ends. During the playsessions of Valtameri the two main characters talk through voicechat, forming the narrative of the game. Each act is bookended by FMV cutscenes, delving deeper into Nina’s mindset.