I thought I knew what was going on here, but I'm at a loss now so there's only one explanation - Valdimar and Rayya are secret lovers.

Quite a number of times now, I have caught Valdimar either leaving Lakeview early in the morning or somewhere between both manors walking in the general direction of Lakeview or Windstad. I had thought that he was sleeping in one of the spare beds because that is the only house, aside from Honeyside, where I have built any, but I just caught him leaving Lakeview again, at 7am (after waiting for two hours), and had the presence of mind to reload and see if he was sleeping in one of the beds... he wasn't. He wasn't in the Armoury, either. He wasn't in the Alchemy Tower, he wasn't in the Enchanting Tower and he wasn't in the Basemant cuddling up to my skeevy little "friend". He just left the house, said "Hail to you my Thane" and toddled off down the road, presumably to go back home, where he should be.

While i do find it amusing to imagine that he is walking halfway across Skyrim on a daily basis for a bit of steamy Redguard action, I can't for the life of me figure out what is really going on, and no, he's not my Steward. Just for the record, before building the spare beds at Lakeview, Rayya used to just stand in the same place all night, the place which is now her bed.

I do have two mods installed, SkyUI and Vilja, but this was happening before I got either of them.

Your Housescal's will travel to all your properties to patrol and watch over them worry not little pattering feet will not overwhelm the halls of your homesteads anytime soon.

I've never had a wandering Housecarl, even in games when I have owned 4/5 "vanilla" houses. In fact, most of them seem to spend their time sitting on their arses munching bread. Rayya wanders (she seems to hunt) but never far from Lakeview, it's only Valdimar that's crossing half the map on a regular basis.