Remus/Sirius
The four of them had explored the castle to the furthest extent Hogwarts would let them as students -- and he firmly believed Hogwarts had let them considering the magic in those old stones. So, it wasn't a difficult thing for him to travel by the fastest shortcuts and passageways from the Clock Tower to Gryffindor Tower. Sirius' outburst at Peter in the journals was sign enough that his friend was having a hard time with this newest reminder of the future that had befallen them. But, Sirius had also admitted it was a lot to take in, which was enough for Remus to worry. James had a handle on Peter for now. When they finished, Remus would check up on each of them in turn, as well.
Skidding to a halt in front of the Fat Lady, he gave her the password they'd all agreed on upon his and Sirius' initial arrival. It probably wasn't required, but it made her feel useful and the added layer of security wouldn't hurt. With a quiet thank you, he slipped past her and into the tower beyond.
"Pads?" he called. "I'm here, now. We can go to the Room as I suggested or stay here. Whichever you need."