I wrote this a while back, but I want to keep it on dA, because my tumblr is a mess...
Why do people write China to be a tsundere?
3chocolatechipcookiesplease: At least in a lot of Rochu fics he's all tsun-y and it's weird because its not how his character is. And it's the same thing with him looking like a girl. When did this come about? Just because he has long hair doesn't mean he looks like a woman. It's kinda annoying, either write the character cannon or put OOC in you fic summary.
What do you guys think?
I think the tsundere part came from the fact that in East Asian culture, it's distasteful and down right uncultured to be openly affectionate with your lover.
I imagine Yao to be more traditional in his view on love, considering the fact that Western influence only started within the last 70 years. In China, it's more about your actions than with words that you tell someone you like them. Hell, you don't even say, "I love you" in Chinese. It's too direct and overly intimate. Instead of saying "Wo ai ni", it's more likely Chinese people say, "Wo xihuan ni" (I like you) and even then, that's not supposed to be said too often or it cheapens the meaning.
So for me, when I write RoChu fanfiction, I think other nations view Yao as a cold and unfeeling person because he doesn't express his affections openly unlike Ivan. They often think the relationships one-sided or Ivan is the one who is more in love with Yao. But behind closed doors, Yao is just as affectionate, but it's a subtle thing like brushing aside a stray hair so he could touch Ivan or adjusting Ivan's scarf because he doesn't want Ivan to catch a cold, etc.
It's due to Yao being used to the Asian way of courtship, (i.e. subtlety, undertones, and implied meanings) he's often flustered when Ivan bursts out his feelings without holding anything back. He's not used to people shouting out, "I love you" to him and so he responds by hiding his embarrassment with a tough exterior.
At least that's how I interpret Yao's tsundere tendencies.
At the same time, I also don't interpret Ivan as a completely open person, either, who exclaims his love. Russians are actually quite conservative people as well, perhaps even to the same degree as Asians. Public displays of affection are only tolerated if it was treated with discretion. However, among those they considered close friends or intimate companions, they converse very closely with each other and often touch each other during the conversation.
So I interpret Ivan's motives for exclaiming his love for Yao, not because he enjoys public display of affection, but because he likes breaking apart Yao's expressionless facade and watch Yao's face blush from embarrassment.
EDIT:
Then again, I sometimes write it where Yao knows what's up and just smiles slyly as he flirts with Ivan right back. For me, it just depends on my mood on how Yao and Ivan handle PDA.