Ryuu: Ron - Vol. 17 Ch. 4 - High Risk Individual?!

[MangaDex]

 

[katajaton]

When Ryu said "in 50 or 100 years, this park will surely remain" I immediately clocked that this must be the author showing his appreciation towards a real life park, and bit of googling later whatdo'yaknow, Changchun Park today looks almost the same as in the manga panel.

 

[Brewers90]

He's anti-Japanese, just like Ryuu (the author's self-insert)