Planescape: Torment: Enhanced Edition

The easiest way to get 25 in an attribute is by spamming the stackable spell Friends (see https://torment.fandom.com/wiki/Friends ) on yourself until you get 25.

The spell can be gotten in the form of a scroll from the first mage teacher you come across: Old Mebbeth(https://torment.fandom.com/wiki/Old_Mebbeth) in Ragpicker's square.

The spell will give you between 2-8 extra CHA points, a lucky two cast will give you the required 25 you need.

Once you switch to being a Mage from the training she gives you, buy her scroll and learn the spell, memorize it in all the slots.

Cast the spell on yourself in quick succession and your CHA should rise, you can make it easier if you also buy and equip tattoos that raise CHA at the parlor.

You can technically do this with the other stat boosting spell that boosts STR but its tricker since it has a max stat limit of 19 (see Strength_(Spell) ) https://torment.fandom.com/wiki/Strength_(Spell)

Cheers.