Perhaps 'One Piece' would suit your taste. It has a vast and colorful world with lots of adventures and unique characters, similar to the charm of My Shiny World. The long-running series offers an immersive experience that could be what you're looking for.
Well, my first shiny Pokemon was a Pikachu. I was just wandering in Viridian Forest, not really expecting anything special. Then, out of nowhere, this shiny Pikachu appeared. I was so shocked and excited. I quickly threw a Pokeball and caught it. It was a moment I'll never forget.
In general, it can be safe if you use it from trusted sources and follow proper online safety guidelines. However, there's always a chance of coming across malicious ads or fake links.