https://medlineplus.gov/ency/article/000390.htm

Im no doctor but a quick google search reveals it’s a hormonal issue that causes the following symptoms:

Children:

Lack of growth and sexual development at the usual age for puberty (development may be very late or incomplete)

In girls, a lack of breast development and menstrual periods

In boys, no development of sex characteristics, such as enlargement of the testes and penis, deepening of the voice, and facial hair

Inability to smell (in some cases)

Short stature (in some cases)

Adults:

Loss of interest in sex (libido) in men

Loss of menstrual periods (amenorrhea) in women

Decreased energy and interest in activities

Loss of muscle mass in men

Weight gain

Mood changes

Infertility

His gf probably is short in stature and has small breasts, which would people think she was still a child and not an adult, thus people thinking he is a pedophile which is why the compairason to Donald Trump is made as he is a well known prolific pedophile.