#!/usr/bin/perl -w

use strict;
use Data::Dumper;

for(grep {/\w/}<DATA>){

	# g repeats the regex, e executes the Perl in the substitution,
	# returns the number of matches into the condition.

	# $1 and $2 are the bracketed matches in the regex in order.        
	unless( s/^(^[a-z ]+) *: *([\w\d]+)/$_{$1}=$2/ige ){
		chomp;

		if (/:/){ # key part
			$_{$_}=join(',',@_); # make new key item
			@_=()
		}
		else { # list part
			push @_,$_
		}
	}
}
print Dumper(\%_);

__DATA__
Graq:
Agnostic:
Number: 634321
age: 27 hair colour: black
height: 73
weight: 123
legs: 2 arms: 2
jameson
bells
guinness
favourite:
detests:
likes: