You'll find a lot of squat-style toilets in Brunei, particularly in public bathrooms.
Western-style seated toilets are the norm in midrange hotels and guesthouses.
You may be expected to flush using water from a plastic bucket.
Toilet paper is often unavailable in public toilets, so keep a stash...
Brunei is very safe for travellers of both sexes.
Saltwater crocodiles are a very real danger in waterways, especially in muddy estuaries. Exercise caution when swimming in rivers, and never swim near river mouths.