First: It could be the pleasure and excitement he is receiving in fingering you.
Second: When you are being fingered if you find this sexually pleasurable your scent you emit gets stronger. Your scent you emit has pheromones or are pheromones which are emitted to arouse and attract a mate. This scent causes you BF to become erect as well.
Third s any visual stimulation he may be receiving while fingering you. For instance if you are naked, or naked from the waist down. Also if you are moaning the oratory stimulation he is receiving also causes him to be come erect.
This is all quite normal. So would your offer to give him and HJ or BJ you would find him erect and ready well before you reached for him. This would normal as his brain would be anticipating your actions. Also very normal.
Teenage boys get excited very easily. It is the new hormones floating through them. I read somewhere that boys get an erection about 4 times an hour. It is an involuntary reaction caused by his hormones hence the word horny. [ adviceman49's advice column | Ask adviceman49 A Question ]
Imperfectionist answered Thursday March 22 2012, 7:11 am: xD uhmmmm hm. Well what gives an erection is different for each guy. It all depends on what turns HIM on. It could be the wetness of your vagina that turns him on. It could be knowing he pleasures you. Or he might just have a fingering girls fetish. Either way, don't worry about it. It's a good thing. And you're getting something out of it ;) [ Imperfectionist's advice column | Ask Imperfectionist A Question ]
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