Tokidoki is just so fun & out there, I don't think there's anything inappropriate about wearing it whenever and where ever you want.
But I personally do see some of my bags as more associated with one season or another. I think of L'amore, Spiaggia and Paradiso as more spring / summer bags. I see Adios Star and Inferno as autumns (I guess because of halloween and the skulls & devils). I'd probably only wear Vacanze during the Christmas season. But I don't see anything wrong with wearing it any time of the year... isn't there that thing about "Christmas in July".