That's Paper, one of Mashima-sensei characters. He's a character in Rave Master Plue's Dog Diary. In the story, he is Plue's owner.
I will tell 당신 the characters one 의해 one. Look at the pic.
- The white one --> Plue.
- The blue one --> Paper. He has no name, just call him Paper. He's the one appear in your question.
- The one eating 바나나 --> Tono. He appear several times in the background of FT anime, like in Erza vs Azuma.
- The cat --> Tamiko. She's one of the 고양이 that Gajeel found when he 검색 for a cat. (
link) She's also appear in the 아니메 as well.
- The granny --> Obababa-sama. In FT, Mashima-sensei made her as Lamia Scale's guild master.
- The 무한 궤도, 캐 터 필 라 below Obababa-sama --> Roji. He's Tamiko's owner and Paper's rival. He's kinda like the antagonist of the series but he's really funny as hell.
The rest are minor characters.
Well, that's it. They appear often in Fairy Tail. Example, in the episode Lucy vs Bickslow. After Sagittarius destroy Bickslow's dolls, he immediately get new dolls, which is the 인형 of Roji, Paper, Tamiko, Obababa-sama, and the 곰 (Kuma). And like I said before, some of them also appear often in FT's 아니메 background (Paper and Tono).
So, stop calling them 'weird creatures' (well, all of them are weird, that's true). But still, they're Mashima-sensei characters :)