Neslo is what happens when you cannot decide between coffee and Milo, so you order both in one glass. Nes for Nescafe, lo for Milo. Sounds genius until you realise you just combined two sweet drinks into one, plus condensed milk on top.
That stacking is why it hits around 250 calories, heavier than a plain Milo ais or a kopi. It is a tasty kaw kaw drink, no doubt, but treat it like the indulgence it is. Ask for less condensed milk and you can knock 50 odd calories off without losing the flavour.