Sanrio characters aren't all peaceful and adorable, and Retsuko is a shining example of this. Sometimes known as Aggretusko, this newer Sanrio character has quite a temper, so it only makes sense that he is found on Mount Hothead in Hello Kitty Island Adventure.

Retsuko is one of the iconic characters from the Hello Kitty franchise whom we have seen in many spin-offs and original shows, and guess what? She has even made her way to Sunblink's latest cozy adventure game,

Notably, you can use the upgraded pizza oven to cook up the Ultimate Joke Pizza, which is Badtz-maru’s favorite gift to get. You’ll get dough for the oven from Retsuko after gifting her items (which surely you are doing everyday, right?) and you can upgrade the oven by befriending Retsuko further.

Becoming friends with your favorite Sanrio characters involves learning their likes and giving them their favorite gifts, all listed here.

Here are all of the locations of each Echo Conches and who they belong to below.

The Opening is the first part of several story quests in Hello Kitty Island Adventure, so here's how to unlock and complete it.

Ziplines are a quick method of moving from island to island in Hello Kitty Island Adventure, so here's how to unlock and repair them.

For instance, Hello Kitty loves Bakery, Fruit, and Fancy tags, so items you gift her should aim to match a minimum of one of these tags. Generally speaking, each tag that matches between a character and an item adds to the amount of friendship XP you'll earn when gifting it to them.