Bhutan id KW 3: 1 image.
Segregating posts due to same subject:
Can you all help me to conform this species
Heterosmilax japonica
It does not match with Heterosmilax japonica as per FoC illustration, Flickr, Flickriver, GBIF, Research gate
Difficult to ID with this image only !
I think it is Aristolochia.
May be A. tagala Or griffithii