No harmful effects--unless the guy has an STD.
Can sucking in your stomach while pregnant be harmful?
nope. sucking to normal girl breast is not harmful
No, Sucking a penis before having sex is not a must. That for his pleasure, not yours.
...yes
sucking patricks penis!
sucking a penis
Usually women would love a 7.75 penis for sucking on a giving blow jobs with, but for sex, they usually prefer about 6-7 inches
yes
You can if the person has an infection.
It's not harmful assuming none of the people have STDs.
Licking clit
Just more pleasure.