#!/usr/bin/perl 

use strict;
use warnings;

use Data::Dumper;

my @persons;
$persons[0] = [];

while(<DATA>) {
    chomp;
    push @persons, [] and next if /^\s*$/;
    push @{$persons[-1]}, $_;
}

#print Dumper \@persons;
print Dumper [grep { $_->[2] eq 'male' } @persons];

_ _DATA_ _
Horst
Mustermann
male

Tina
Mustermann
female

Otto
Mustermann
male