Characters
You play Hugo, a rookie PCD officer; his new partner Ray and researcher Lucia anchor the office cast, while Onna and Silvia carry over from the visual novel.

The cast, who's confirmed where
The series has a small, deliberately odd cast, and the prequel shuffles who you actually play. This page tracks who is who across Project Jupiter and the visual novel, and flags what is confirmed versus what is still community reading.
| Character | Where | Status |
|---|---|---|
| Hugo | Project Jupiter (protagonist) · VN | Confirmed |
| Ray | Project Jupiter (partner) · VN | Confirmed in both |
| Lucia | Project Jupiter (PCD researcher) | Confirmed |
| Silvia | Visual novel | Confirmed |
| Onna | Visual novel | Confirmed |
Hugo — the rookie
You play Hugo, the newest officer at the national Plague Control Department. The official screenshots define him before you even see his face: the receptionist greets him with "You must be Hugo, right? I saw your photo early, so this is more of a rhetorical question. Of course you're Hugo! You have a Hugo face!"
He is also part of the VN's cast, which means the prequel shows you where he started — a recruit with a desk, a badge, and no idea yet how bad the job can get.
Ray — the partner
Project Jupiter pairs Hugo with a colleague the store description openly calls a partner "it's difficult to trust." Veteran players of the visual novel will recognize the type — and possibly the name carries weight for those who remember where Ray ends up. For newcomers: watch him. For veterans: you already know why.
Lucia — the researcher
Lucia appears in the early PCD office material: she is the one standing at the whiteboard explaining that the department has been studying the infection "for a long time." She is your primary source for what Mycopsychosys actually is — the disease has its own dedicated page here.
The displaced regulars: Silvia and Onna
Silvia and Onna belong to the visual novel's side of the series — Onna's story is wrapped around the infection itself, while Silvia appears throughout the Remastered edition's redrawn art. Because Project Jupiter is a prequel, expect the connections to run backward: characters you meet here may matter far more a game later.
Office furniture, basically people
The screenshots also show unnamed staff — most memorably the pink-haired receptionist whose name tag literally reads "Woman". The departments in this world are small and every desk has a personality; part of the game's charm is that even the setup session is fully cast.







