The Green Dumelet.
I have checked Dumelet's gene-splicings and he does indeed glow a most delightfully leprous green under ultraviolet light. I have therefore installed these throughout the castle, with motion activators because there's no sense spending money on places he's not in.
Senga has been using them to top up her tan. As a result, she now resembles a skinned crab with blisters because these lights are not intended for the purpose she has put them to. It's not such a big deal for me because she looked pretty crab-like before apart from the total whiteness and the number of legs. She already had the propensity for picking slimy molluscs off the walls.
All the same, she insists it's painful and was not amused when I took out my clipboard and requested details. She has taken to sleeping in one of the spare rooms and won't tell me which one. Well, it's up to her but if Dumelet escapes his cot I won't be able to tell where the screams are coming from.
I'm keeping the barbed steel bed-net though. She can take her chances with Dumelet's night hungers.
