My question is that in Jannah, will one be permitted to watch porn or live sexual intercourse of others for one's own pleasure, or are such things prohibited for believers in the Hereafter as well?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.

The wishes and desires of the inhabitants of Paradise are dramatically different from those of the people in the worldly life. People are admitted to Paradise after they had been purified and cleansed. Their characters and manners are refined, and they become genuinely good. They honorably refrain from what sound human nature rejects and what is reprehensible and shameful. Indeed, looking at pornographic images is an example of such shameful and disgraceful acts.

For further information, please refer to Fataawa 83922 and 45862.

Allaah Knows best.