We've climbed in Kaly for the last two summer. Last year, the meltemi blew from the north most of the time so the temperature never really got much above 30 degrees. And to be honest, with rock as rough as Kaly, this temperature isn't so bad... as long as you are in the shade. It's not like trying to climb on British limestone at this temperature (oh horror!). You might find some of the more slabby routes with slopers or small crimps tough going eg Paris Texas or Moonbridge but the more usual steep-but-juggy fare is fine; for example, Marci Marc saw lots of ascents in August. Those accustomed to the temperature (ie Greeks and Italians) were putting in the time on routes up to 8b.
As far picking up a partner, you'll be able to put a note up on the notice board at one of the two climbing shops though, as noted above, most of the summer climbers are from the Mediterranean countries.