What does this ant want?

And how do I make its friends leave my house?

It's not the dry season so they're not here for water. All food is tucked away. I can't find any sign of them under my house or on the roof. There are no visible clusters of them or trails of them (except the first two days of using Terro and then they started ignoring it) and in the morning clustered on my bathroom night light. They also ignore borax and honey and borax in peanut butter.

It's like the roamers just enjoy hanging out in my house, stretching their legs. I'd prefer they don't anymore.  

I'm not currently in a house where I can possibly seal up every gap and hole.

how big is it?

Bigger than sugar ant. Smaller than carpenter ant.