Should I get a male or female pet?

Honest answer: for most species, individual personality matters far more than sex. There are gendered statistical tendencies, but the variance within each sex is bigger than the difference between them.

Dogs:
- Males average slightly bigger and slightly more energetic in many breeds, but not all
- Females are sometimes (slightly) more independent
- Marking and humping are not "male behaviours" — both sexes do them, neutered or not
- The biggest behaviour predictor is not sex but breed, early socialisation, and the individual dog

Cats:
- Males tend to be more sociable and seek human contact more often (statistically)
- Females are sometimes more reserved
- Once neutered/spayed, the difference is largely gone
- Unneutered males spray and roam — neuter early (around 5–6 months)

Multi-pet households:
- Two males or a male/female pairing usually work better than two females, especially in cats
- Two dogs of the same sex CAN work — dependent more on temperament than gender

What to actually pay attention to instead: meet the animal, look for matching energy with your lifestyle, ask the breeder/shelter about specific personality traits (chill / busy / sensitive / pushy), and prioritise that over sex.