That Russia has a completely loving relationship with his big sister and a completely hateful relationship with his little sister.
Even Hetalia won’t totally whitewash that in real life, Russia and Ukraine have rocky relations. Even if Ukraine herself is too sweet to yell “eat shit and die” at her little brother, the notes in the manga clearly speak of Ukraine’s anti-Russia sentiment. Russia believes Ukraine hates him. He puts pressure on her. Ukraine still loves and cares for Russia, but she wants to make friends in the EU. She also left Russia after the Soviet Union collapse on her own terms, with no apology.
And Belarus? Sure, she’s a psycho and Russia is disturbed by her stalking behavior. But he was happy when she came back to support him after the other ex-Soviets left him. They can get along peacefully, like when they were discussing Russia’s comfortable chair. Belarus tends to serve as Russia’s sidekick, threatening and intimidating others to satisfy what her brother wants. And well, he doesn’t seem to mind.
[ aaaaaa ]