Like other ships of her generation the Erytheia's hull is painted light blue.

The captain's suite is a luxurious cabin located on deck two, forward of the bridge. Inside, the thick, soft, red carpeting matches that of the lounge. The room is lit more dimly than the rest of the ship using several lamps placed throughout the interior and studio lighting rather than the normal ceiling lights. There is a very comfortable bed, a medium sized wooden dresser, large bookshelf and a cozy reclining chair (to give some idea it is a similar interior to this). There are two bonsai and several other plants to freshen up the cabin. A large custom walk-in closet with shoji/fusuma doors is located at the rear of the room (going towards the bow), along with a tiny bathroom.

Ryosuke also added sevral more pieces of furniture including an office desk engraved with the ship's plaque. The panel underneath the plaque opens up to allow access to the data terminal hidden within.

The ship's bridge has the ship's emblem in the bridge carpeting. Also the Starship Ops station at the front of the bridge has a SPINE interface.

The Erytheia's wardroom is located on Deck 1. It contains round booth tables in the corners and rectangular tables in the middle section (which contain cast iron grills for teppanyaki cooking). A Standard Star Army Galley and scullery are adjacent to it. The amenities Ketsurui Fleet Yards had been kind enough to build into it include marble floors, leather seats, and a ceiling made up of paintings of famous Star Army officers in scenes of their most glorious moments. An elaborate staircase runs down to the lounge. There are Bonsai trees placed behind the two booth seats.

The Erytheia features a Sakura-type Medical Laboratory on deck 3, forward of the power armor bay.