The place from where nexon takes ideas for new pets

Not really.

Panda/Husky/Pig/Elephant/Monkey/Kargo were all in KMS before this.

GMS didn't come up with the flying pig.

CMS did, for Chinese New Year- Year of the Pig

Only pets GMS came up with are

-Duck
-Crystal Rudolf
-Porcupine
-Skunk
-Blue Husky
-Black Bunny
-Orange Tiger

Unsure-
-Snowman
-Turkey
-Jr Balrog
-Robot
- Jr. Reaper

Not sure if we, or KMS came up with the Pets listed in "unsure"