We found it very difficult to concentrate on our studies whilst horny.
Then there was a time in my study. At the time we were trying hard not to get pregnant. I was sitting there studying, naked under my bathrobe. I had a plastic study chair with no arms. She came into my study with her hair wet, also naked under her bathrobe.
She opened my robe and knelt down to suck me. When I was hard and eager, she removed her robe and sat on my lap, facing me as I sat in the chair. Her knees were wide apart, at my hip bones. We both had easy access to each others privates. She was kissing me, and stroking my throbbing dick. I was kissing her neck and my fingers were massaging her pussy, first probing her vagina then carrying her lubrication up to massage her firm clit.
First she came. Then I asked her to finish me mercilously. She transferred her own secretions to the throbbing head of my cock, then stroked the base tightly with one hand, while with her other fingers she quickly massaged the large purple head. When I came I must have shot a quarter-cup of jism. It was all over her breasts and belly, and pooling on the plastic chair between us.
She mopped it all up with several handfuls of issues. When she left I went back to concentrating on my math study.