This is my favorite Grimm episode simply because this folklore originated from our country(Philippines). It is about "aswang"/(creature who feeds and preys on pregnant woman and suck fluids in their stomach, and some believed to eat the unborn baby too.) The episode also used a little bit of our native Filipino language and also showed a part from Manila, Philippines :-)
This episode was contributed by Reggie Lee(Sgt. Wu) who I just found out is half Filipino! In an interview he shared that the writers of the show asked him if he knows any Filipino folklore/urban legends, and he gladly shared the myths about aswang.