What does it matter what the guy thinks ?
If you want to have sex with the guy, then have sex with him. (just take precautions).
That the guy might think you are "easy" or a "slut" should not factor be part of the equation.
If you don't want to have sex with the guy, then don't.
Sex is not something the woman does so the guy will love her etc.
And sexually women have needs also. The guy should respect that.
From the way your question is worded, It seems as if you feel pressured.
If you are not comfortable having sex, then don't. So don't feel pressured either way.
For the guy, have sex with a woman that does not really want it, is not very good sex

And any guy or girl who pressures another person for sex is an butas ng puwit

Many men seem to have an unhealthy attitude towards sex.
Sometimes I think it is more about dominating the woman as opposed to actual pleasure.