|Allegiance|| House Belmore|
House Royce of the Gates of the Moon
|Book(s)|| A Clash of Kings (mentioned)|
A Storm of Swords (mentioned)
A Feast for Crows (appears)
Marwyn is lanky and has red hair.
A Clash of Kings
A Feast for Crows
Marwyn is removed from his position upon the arrival of Lord Petyr Baelish, and he is replaced by Ser Lothor Brune. He returns to the Eyrie to hear Marillion confess to the murder of Lady Lysa Tully. He despises Marillon as Marillion mocked him in song as "Ser Ding Dong". Marwyn now serves as the captain of the guards in the household of Lord Nestor Royce.