Where to shop for men’s trousers in Tokyo?

Looking for black trousers in the elevated relaxed fit that I see a lot of the young local guys wearing. Any stores that are good for these? I’m a 28W 30L so hoping to find better fits in Japan than the UK where everything is too big.

Staying in Asakusa if that helps (I bought some denim from the market 2K540 in Akiba earlier which I love).

Is Gu any good? Uni Qlo doesn’t work for me at all.

by ftatman