Oh maybe instead of Portal, it was a Super Mario Brothers reference. And when she said "cake", she really meant sex.  
... 
Yea its probably a Portal ref. You seem to find a lot of those in games you wouldn't expect to. The one in Castlevania was a bit of a stretch, though.

I over heard a long time ago, from someone whom I meet at a party who said he once met a guy in a bathroom in Taiwan who said he knew a guy who sat next to the girlfriend of the guy who cleans the pool of the neighbor of one of the developers at Valve that worked on Half Life 2 who knows a guy who knew one of the developers of Portal when they were in kindergarten who told him that the cake is in fact...

Every game nowadays has a Portal reference...

Guh. Sounds forced. I'll reserve judgment for if/when I play it myself. But... guh. It sounds forced.

They also included the line "that's what she said" :(

You know, I liked Portal but I'm getting pretty sick of it now. Its was a fun little game but the way everyone keeps going on about it is uncalled for. It wasn't that good.

I love Easter Eggs and References.

There's a BioShock reference in Mafia 2. Devs are sneaky motherfuckers.

" You know, I liked Portal but I'm getting pretty sick of it now. Its was a fun little game but the way everyone keeps going on about it is uncalled for. It wasn't that good. "