For some reason, I had trouble with your code. Instead I turned the problem on it's head. 
use strict;

my $lines = do{ local $/; <DATA> };

# reverse the order of the lines so that the RE matches the
# last part of the region first
my $reversetext = join("\n", reverse(split("\n",$lines)));
$reversetext =~ s/^[^\n]*e p.*?s[^\n]*\n//msg;

# put the lines in normal order again
$lines = join("\n",reverse(split("\n", $reversetext)));
print $lines;

__DATA__
Random String
s
erartt
e p
s
foo
e f
blah blah
s
adflkja
wibble wobble
e p
End of file

[download]

==
Kwyjibo. A big, dumb, balding North American ape. With no chin.

In reply to Re^3: Matching and replacing the minimum string from the tail of the regex by abitkin
in thread Matching and replacing the minimum string from the tail of the regex by abitkin

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