The annexed grave chapel, the Parecclesion, built by Metochites, lies alongside the church and ends with a wide arched apse. We reach here by passing through two narrow columns. The columns further ahead have more slender bodies, and carry elegant capitals. Light pours in from the windows of the dome at the middle of the nave. In the side chapel called the Parecclesion, on the marble slab placed on the arch at the right of the middle of the chapel, an inscription is found.
In the Parecclesion, there are four grave niches counter each other and two passages. The first two niches in the south and the north are embellished with pieces of marble ornaments belonging to earlier periods, and used again later on. At the first niche on the front, we find mosaics and frescoes of Mikhail Tornikes and his wife, who are buried here. The annexed chapel is divided into two parts by a marble freeze. At the bottom, the soldier saints are depicted. Important members of the church are portrayed in the apse.
Frescoes were most likely made by the masters who did the mosaics. At the first section of the chapel, when standing against the apse, one can see that many important scenes from the Old Testament are dealt with.