Nite Ize S-Biner MicroLock Stainless Steel - S-Biner with Locking Dual Sided Gates - Keep Keys Secure with Carabiner Key Holder - Black (2 Pack)

I don’t have IBS, but do use the restroom fairly frequently. I usually try to do these things: - If your budget allows, go first class. Fewer people in the cars and easier restroom access.- Get seats in the middle of the car, away from the doors. It’ll be a little harder to grab and run from there.- Figure out the long stretches without a stop, try to schedule breaks during those.- Keep the most important items on your body when you go. In my case, passport, phone, wallet, and a small case with a few days of prescription meds.- For added security, get a cable lock like this one that you can attach the bag (if possible) to the overhead shelf. Be aware, though, you better have it off and ready to go before you arrive at your destination.- Place your bag with the opening facing in, away from the aisle. It’ll slow someone down from quickly unzipping your bag and grabbing something.- Use lockable S Biners to lock your zippers.

Probably just me being paranoid but I’m always worried someone might go through my backpack when I’m not paying attention. I got these to put through my zippers so it can’t be opened unless you’re REALLY trying https://a.co/d/0824fOSb

You could try switching that regular para cord for micro para cord and use a mini S-beaner like these https://a.co/d/0638JUSc Amazon link.