When you (1) go on an all-out synth shopping spree (got 4 synths over the summer - 3 Roland/Edirol, 1 Yamaha) partly due to wanting to learn ZUN style and (2) decide to name them all after Touhous.
I've named my tabletop synths after the Prismrivers - Merlin (SD-90, thanks to the ZUNpets / Romantic Tp.), Lyrica (MU1000, good general-purpose synth), and Lunasa (SC-8850, unusually potent for orchestral works).
Should I go for portable synths (namely MU500 and SC-8820) as well, I'll name them and the SD-20 (also mobile) after the Three Faeries as well.
And if this expands to pro-level synths such as Fantoms and Motifs, they'll be Kaguya and Mokou, respectively, owing to Roland and Yamaha hating each other's guts (even goes so far as to have few Cakewalk INS patches for Yamaha synths, and few Cubase Patch Scripts for Roland ones).