After 203 eggs, I got my first Shiny since I got the Shiny Charm in my copy of Sun: a shiny Fomantis. Bred to have an Adamant nature and its Hidden Ability Contrary. He is nicknamed Coronatus, after part of the scientific name of the Orchid Mantis (Hymenopus Coronatus). He got 5 perfect IVs, only missing Special Defence. It's not entirely perfect (would have preferred it to be missing Special Attack rather than Special Defence, in all honesty), but it'll work for my Ultra Moon team.
Next up, I'm going to do a random encounter hunt somewhere in Alola, in preparation for a Badge Quest I'm planning to do on Crystal soon.
EDIT:
Well, this is unexpected. Just 22 hours after my last shiny, and after just 429 REs on Route 2, a Cutiefly shined for me. A pleasant surprise, especially as it's one of the three I was hoping to find on that Route. However, I was kind of hoping for a slightly longer hunt to increase my patience ahead of my Crystal Badge Quest, but I certainly won't complain about another shiny so soon.
He's a Level 8 male Cutiefly called Flybee, with a Naive nature and the Honey Gather ability. Other than having a perfect IV in Special Attack and "Very Good" in Speed, his IVs are nothing to write home about. But that's fine, I suppose.
Going to Masuda Method for a Shiny Durant next, which should keep me satisfied until after my exam on Tuesday and before I go and start Ultra Moon on Wednesday (and then maybe Crystal next weekend).