Shibuya, Tokyo is notorious for being packed on most days, but during Halloween it gets even more absurdly crowded. I missed Saturday night, which is the busiest, but even late on Sunday the place was at capacity. The streets are closed off to traffic and you see a lot of police around, but everything feels very peaceful.
The Japanese take on Halloween is of course a bit different (as is their take on Christmas, Valentine’s Day, etc.). In particular, costumes are highly coordinated – you will typically see groups of 3-6 people dressed exactly the same way.
Anyway, I’ll let the photos speak for themselves.