Well, he could summon an NPC of mine from a different game system....
For the In Nomine game, I created an ethereal that was a water elemental that owned a bath/spa/jacuzzi artifact; rewritten for the Dresdenverse he'd only need to have Swift Transition (No Mortal Home), a high Craft skill (specialising in massage) and the ability to grant the Aquatic Power (say, put that in the Jacuzzi Item of Power).
The only payment Laver would want would be the Fate point to 'loan' his IoP to his bather.
Laver would then hang around until he was next summoned.
here's the write up in the IN rules if you're interested:
Laver
Primal Bath Spirit
Corporeal Forces: 1 Strength: 2 Agility: 2
Ethereal Forces: 4 Intelligence:10 Precision:6
Celestial Forces: 1 Will: 2
Perception: 2
Element: (Classical Elements) Water.
Affinities: Water(Primal), Fire (Moderate),
Glamour(Moderate),Entrancement (Slight).
Vessel: Large body of water/3, Charisma +3 (Bath -
Essence cost: 150)
Skills: Artistry(Massage)/6, Knowledge (Hell's
royalty/3).
Rituals: Summon Named Ethereal Spirit.
Dread: A disappointed bather/4.
Attunements: Partial Celestial Attunement(Lilith).
Artifacts: Talisman(Artistry{Massage}/6); is also an
endless supply of bath salts and oils. Takes the form of a bath, spa or jacuzzi as desired.
Countless cold, dirty, miserable humans have dreamt of
a nice warm bath - and their dreams spawned Laver.
Laver has no particular agenda: all it wants is to
help people relax and be clean. It's very good at
this; bathers frequently fall asleep, as the water
massages the tension out of them - so Laver simply
grants them the ability to breathe underwater.
Laver's name can be found in numerous sorcerous texts,
with the simple deal Laver offers - summon it and
provide the 5 essence it needs to power it's
abilities, and you will be delightfully pampered.
Sorcerers in the know consider Laver one of the most
useful spirits to Summon - any spirit can grant power,
but Laver makes life worth living.
He's also a fine way to Damn your soul, although that
wasn't his idea. Lilith was the first Superior to
learn about Laver, and swiftly granted it the ability
to Summon her - if she's going to listen to sorcerers
offering deals, she may as well do so in comfort.
Besides, most sorcerers' brains melt when they see
Lilith bathing, which makes them so much easier to
manipulate and out-bargain. Andre and Eli are also
regular patrons - Laver grants +4 to any attempt to
Invoke any of these 3 Superiors. (Kobal has been known
to captain ships whilst bathing in Laver, but that
joke has apparently gone stale).
Laver is probably doomed - "Prince Andre is so nice!"
Although Lilith is trying to keep Laver free (with aid
from Eli, Marc and Yves!), Andre is determined to have
Laver's services permanently at his disposal. If
(when?) Andre succeeds, he intends to add 2 Forces to
Laver, one from a Balseraph and another from a Djinn;
then add his appropriate Band Attunements and the
Sensitivity Attunement! Of course, all of this
Infernal power is likely to warp Laver, but Andre
doesn't care.