# Read names, extracting what's after the dot and before the end of line
my @names = map /\.(.*)/, <DATA>;

# Shuffle the list
use List::Util 'shuffle';
@names = shuffle(@names);

# Print them out two by two
for (1..@names/2) {
  print "Group $_: $names[$_*2-2] and $names[$_*2-1] are partners\n";
}

__DATA__
1.bobby
2.jane
3.charleen
4.markus
5.gabriel
6.Alex