If it turns out to be a Peperomia, it may be an introduced plant to Singapore.
Try to look at these to see if there is a similarity:
P. hoffmannii, whorl of 3 leaves at node:
http://succulent-plant.com/fam...
(
I aplogize; my computer is too slow today to add more links for the others.)
P. catherinae
P. isabella
P. deppeana
P. pellucida
P. verticillata