Fleet Captain Tassa Riese was raised on Imiron. She is the commanding officer of the Fiat-class battleship ICS Shrike. She also commands the Sixth Fleet's rapid strike battle group, which is available to all the fleets in the Imperial Navy.
Riese is both steadfast and incisive, and although she is sometimes seen as risk-averse her priority is always to understand as much as possible about a situation before throwing herself into it.
Tassa Riese was present at Fort Laeara for the Operation Seawall briefing given by Admiral Groath Betombe, during which she asked several probing questions about the overall strategy which he outlined. She later took part in the operation itself, at the Battle of Gousk (→SFTD).
Shortly after Operation Seawall was declared a failure Riese was recalled to Ramm Stallahad, where some claimed she had a mysterious meeting with Fleet Admiral Tabius Bel-Messari (→TRD).
Captain Riese was used as an example by Betombe during a conversation he had with Captain Aker Santani, in which he wished to explain the underhanded politics of some flag officers. He suggested that Tassa Riese had been after a role in the admiralty for some time, and that if gaining such a role meant torpedoing his career and leaving the Sixth Fleet behind, then that is what she would do (→TRD).
While that might seem like a cynical and unkind suspicion, it was likely correct. Captain Riese was seen by Betombe to leave a conference chamber on Fort Sol, immediately before he was called into the same chamber to face a triumvirate panel (→TRD).