(Video link) If you've not done this or got lost halfway, here's a guide following the Seelie's trail. Consider trying it yourself first after watching the start location (The journey is fun! You could favorite this post and come back later if you're lost :p ) There'll be a Luxurious chest and 2 Precious chests for your effort.
Link: Electro Seelie chase around Watatsumi
Tip: Changing to "Night" time (after 7pm) makes it easier to spot the Electro Seelie!
#gameguides
