Belen Pappas best friend, they have been in the same division of Sector Security from the start. Delis grapples with a profound hatred of Nova Nacio. His father once was part of a joint effort between Kalymnos and Nova Nacio to build new starlanes. When the Nova Nacio pulled out of the project, Delis's father was ruined; he subsequently commited suicide. Since then Delis has held a grudge against Nova Nacio, refusing to forgive them, work with them, or show them mercy. When the war breaks out with Nova Nacio over Irvest Sector, his friendship with Belen Pappas is strained to the limit.
Valas tells Delis about "Plan R" very early on. While doing missions, Delis demands Yuri act on information that only Delis is privy to. Eventually, when Plan R is revealed, Belen Pappas convinces Delis to do the right thing. He will tell Yuri how to counter the falling satellite, and eventually makes the ultimate sacrafice. Belen Pappas finally makes up with him and joins him in using the Stellalumos Laser... surviving the incident.
It is possible to recruit Delis back into the crew after he sacrifices himself. After completing the Irvest War subplot, instead of immediately proceeding to Kashtano, if the player instead heads back to the previous sector (where the player formally joins the Kalymnos forces) it is possible to replay the conversation with Glavanis. During the course of this conversation, Delis will join the player's crew, and the player will recieve 5000 G, just as they did at the start of the chapter. The player is then able to continue the game as normal, except the Lykourgos will not join the player's fleet when they enter the Magellanic stream (although Celina will appear in dialogue with Pipra as normal).