Substitute numbers for letters (same letter, same number; different letters, different numbers) so the following equation works out:
KISS × KISS = PASSION
K= 2, I = 0, S = 3, P = 4, A = 1, O = 8, N = 9 <p>
2033 x 2033 = 4133089<p>
A kiss is just a kiss, but the result of two kisses is passion.