"Having bad proportions is the point of the character (in fanart)."
Whut? Well, how about flagging everything from that character then :>?

(Not the flagger)

again what proportion? is it that exaggerated calf? if that's the case, well, like i said it's exaggerated. just like the whole picture in general. ryouka's body here is exaggerated in general(calf, thigh, curvature, and breasts...as if it's not exaggerated enough on the source). even the concept of ryouka slams the poor dude with the sheer weight of her breasts is ridiculous.

this is the type of artwork you should not judge the proportion too seriously as it's not trying to be 100% anatomically correct.

If every post got flagged for anatomy issues, almost nothing would get by the moderators. There is willing suspension of disbelief, then there is artwork that just looks bad regardless of its style or if it's trying to be "correct". It's all about consistency.

I think this flag is pointless based on the sole fact that this is actually close to what the character looks like.

Well, after looking at this post multiple times, I think that the real problem is more that she has breasts that are made out of some material that defies gravity (since they don't go downwards but ok, she is in a movement, so that's that and not the conent of the flag.
Proportions problem...can't really see them. Arms are ok, head size is ok, legs are ok. Breasts...well, it's still acceptable.