Sunshine City in Ikebukuro is a large shopping and entertainment complex that I’ve probably been to over 100 times in my life. It’s a well-known spot, especially if you’re into anime or Japanese pop culture. Inside, you’ll find the Pokémon Center Mega Tokyo, the One Piece Mugiwara Store, and a number of other character shops, including Sanrio and Ghibli-related stores.
There are also frequent pop-up events and weekly attractions—some of them tied to seasonal campaigns, idol groups, or anime promotions—so there’s always something new going on. The complex has plenty of food options too, especially casual cafés and dessert spots, along with outdoor gear and lifestyle shops.
It’s not necessarily a “must-see,” but if you're already in Ikebukuro or enjoy anime, character goods, or just browsing a wide variety of shops and food, it’s an easy and entertaining place to spend a few hours.