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Retard-kun, buy trousers or cargo pants with spatious pockets and maybe velcro/buttons/zippers on them.
If you are more paranoid, there are "belts" of sorts made to carry stuff and wear them under your clothes
For self-defence, 99% of the cases the best idea is to either comply or run away. If for whatever reason you are fool enough to stand up to someone, look for a good steel flashlight, with it you can slightly dazzle someone (at night), strenghten your fist like with a pack of coins or just hammer someone with its ends. Still, better to run or comply.