g for go

g for go

ご is the number 5 in Japanese
without the two little lines on top of go would be ko.

So the following are the numbers from 1 to 10 in Japanese Romaji

1-ichi 
2-ni
3-san
4-shi/yon
5-go
6-roku
7-shichi/nana
8-hachi
9-ku/kyuu
10-juu