How many packs of cigarettes?

Earlier on I was out of ideas on what to give my x-roommate's 29 y/o sister in Japan. I am glad that she replied my e-mail answering what she wants.

She wants me to get her local cigarettes (handed to her when her parents are out of sight). As I am not a smoker, I am wondering how many packs would a Japanese smoker be happy to receive?

I also think it's best if I give her a "dummy" gift on top of the cigarettes so her parents won't get suspicious. I am thinking of giving sweets as the "dummy" gift.

Any opinions will be appreciated. Thank you.

You don't know if she will like it, so I would say 2 or 3 kinds, one each, just as a sample.