2 players 1 PC

Hey guys, I've built myself an awesome machine that I want to show to my significant other, and I want to do that by getting us a 2 player game that we can play on 1 PC without additional controllers.  

Can you guys help me out? Got any recommendations? 

[Perhaps some useful info] So far she played Portal 2 with me (but she wasn't into it, a lot), also she played some Warcraft and Sims when she was a kid

Trine 2 comes to mind.

https://www.youtube.com/watch?v=PVs1Zv32q18

Easier to set up if one player uses a simple controller of some kind, but can be played with multiple keyboard/mouse according to some guides. Playing the wizard character is definitely best with keyb+mouse.

Looks good, I'll check it out

Here is a list of local (multiple players, one machine) multiplayer PC games

http://pcgamingwiki.com/wiki/List_of_Local_Multiplayer_Games

Thanks, got any one of those to recommend for me ?

Trine 2, Serious Sam 3, and Portal 2 are all good games that I'd recommend, but a lot of the other games on that list are pretty good too