If you zoom in on the can it says 6%. Japan went through a phase of increasing alcohol percentages on these types of drinks ~10 years ago when the govt was raising taxes on beer a few times in a relatively short time period. They first came out with the "strong" versions which were 9%, and I think that wave peaked at a 13% lemon drink (which tasted like licking a robot, btw).

More recently Japan's been a little more health conscious about booze in general, so there's been an increase in types of non-alcoholic versions of drinks, including pale ale type beers and cocktails. The companies making cheap options like the -196 and the zeros have subsequently put 6 and 7% versions in the stores. There've also been studies showing young people drinking less overall, so it'll be interesting to see what the next moves are.