Can I re-enter Japan during my 90-day visa?

Hi all! It's a pretty straightforward question. I'm in Japan for 89 days and decided I want to take a week-long trip to South Korea within that timeframe. Is there anything special I'd require regarding re-entry into Japan, or am I good to go as long as it's still within the bounds of my intended 90-day stay? Thank you!

If you are from a visa-free country, with a temporary visitor status, yes, you'll just get another stamp when you get back.

And if your not from one of those countries. You'll need to ask immigration if you can get a re-entey permit when you exit the country.

@H ..

That won't work if OP is on temporary/tourist visa.
Special re-entery or re-entry permit is only for those with resident status/zairyu card.

OP..
that depends on whether you are from visa waiver country or not.
Visa runs is good for visa waiver countries BUT whether you are allowed to enter Japan are at discretion on immigration officer.