Since Daiyousei is a "big fairy", the guy is going to play with her with a dildo, and that weird enema syringue. And she's not happy about it. The joke here is that Daiyousei is still an innocent and underage fairy, but the guy is going to rape her. Wait, that doesn't sound like a joke when I say it like that...
There's also a pun involved:
ThunderBird said: Commentary: The "Big" in "Big Fairy" means "Loved Fairy", right? Hehehe
Sigh. I understand the urge to make an educated guess on something you don't understand, but you really need to check the Pixiv tags and do at least a cursory web search before doing so.
The pun is that instead of, say, 'number 1' and 'number 2' as in English, the Japanese euphemisms are 小 (small) and 大 (big), from 小便 (urine) and 大便 (feces) respectively. So, poorly:
The "big" in "big fairy" means "a fairy who likes to go 'big', doesn't it
glasnost said: Sigh. I understand the urge to make an educated guess on something you don't understand, but you really need to check the Pixiv tags and do at least a cursory web search before doing so.
Not everyone can read Japanese. And last time I tried to use Google Translate, it talked about waffles, Orange, Purple and cupcakes.