[Source] Louis Merse is a secondary character in The Witcher 2: Assassins of Kings. He seems to be very fond of forms, in particular, form WL-17 (for The Endrega Contract), form THX-114 (for The Nekker Contract), forms H-12 and AR-12 . Spoiler warning: Significant plot details follow. Later on, when Geralt finds Dmitri and kills him, you can find a report on him, revealing that Merse and Loredo are involved in the local fisstech traffic. Also they are covering for criminals like Dmitri. The safeconduct letter found on Dmitri also confirms this. Significant plot details end here.