Is he cheating or not?

So my bf has his own place and I'm not there full time and he has condoms in his nightstand, well I specifically remember seeing one that was ripped apart from the rest and remembered having at least 6 left well today I found only 4 and when I confronted him he said he used them to masterbate with because they were fire and ice?! So what do y'all think? Cheating or being honest??