Where to go after 9pm in Narita 17 year old

i'm going to Japan for my graduation gift on July 30th and i will arrive on July 31st at 9pm. i'm only 17, so when i tried to book a hotel, at the 9 hour capsule, it says you have to be 18 years old when you check in.

i just need a plan to stay over night until the morning because my friend who lives in Japan will pick me up.

i heard there is a 24/7 grocery store or convenient store in Narita, so i was think of staying there awake until the morning, unless i can get a hotel somewhere?

i know it is not allowed to sleep at the airport. any ideas? thank you!

i know it is not allowed to sleep at the airport.

Some areas of the airport are now open 24 hours, and you can stay there overnight. The number of 24 hour services is increasing. Every terminal now has at least one convenience store that is open 24 hours. Terminal 3 is particularly overnight-friendly:

Terminal 1:
http://www.narita-airport.jp/en/guide/index_t1.html

Terminal 2:
http://www.narita-airport.jp/en/guide/index_t2.html

Terminal 3:
http://www.narita-airport.jp/t3/en/index.html