Butterfly & Ants feeding on Aphids

This is a subspecies, Allotinus fallax fallax.
When I first spotted it, I had originally thought the Butterfly was under 'attack' by the ants but on closer look, I realised both the Ants and Butterfly were feeding from tiny Aphids.

In the picture, although not very sharp, you can see the proboscis of the Butterfly extended and is feeding from the back of the tiny Aphid.

Feedback from another forum, Philippine Lepidoptera mentioned this :

A species which belongs to a genus of butterflies in which the caterpillar stage is "carnivorous". The caterpillars feed mainly on aphids but also sometimes on coccids, psyllids and membracids. As adults they feed on the secretion directly from the backs of the membracids.