This is completely unpredictable. But, don't worry hair will grow in all sorts of places before you turn 20. :) Yes, you're underarm's hair comes around when you're 14 or 15, and you get the puberty on you're penis when you're 11 or 12, don't worry about it it'll come soon.
under armpit hair no it doesnt matter which comes first, puberty is different for everyone so u could have pubic hair first or voice breaking, or penis growth, or something else.
By 18 he should have long had pubic and armpit hair. He may still have some growth in him but that is about over. Kinda scary you know his penis size.
well, most boys don't, but it happens to some boys, nothing to worry about.
nose, penis, toes, armpit
He probably has some. If armpit hair is growing then he has started puberty. This will happen to you soon. During puberty you will usually have a growth spurt, that is, you will grow taller rather quickly. You will develop muscles. Your penis will also start growing so that by the time you are 16 or 17 it will reach its full size. Remember everyone is different. Be patient and don't worry.
There is nothing secret in puberty. Except the growth in your testis, penis and breasts.
that depends on his motives
I don't think that armpit sex is an actual thing...but my guess would be that you would either... 1) Rub your armpits together so that they hump eachother 2) Stick your penis or vagina into someone's armpit
The first noticeable sign is normally pubic hair growth, followed by armpit hair. The boy will start to get erections, and his testicles and penis will grow in size. Following this, he will start to be able to produce sperm, and ejaculate. The final stages are voice breaking, muscle mass increasing, and broadening of the shoulders.
Ok you are starting puberty at 13-years-old with a penis measuring 6'' erect and you are worrying about no growth. First of all your penis is above average erect for your age anyway so any growth will be small and over the period of your adolescence up until around 20-years-old. Secondly the average size of a penis flaccid (non erect) your age is about 2-3'' and an adult 3 1/2 - 4''. The average adult erect is around 6'' You don't need to worry about it's growth.
A male penis will grow the most between the ages of 12 and 18 it will stop at about 20.
They are all for women's entertainment and warmth
Yes, penis does affect radiation.