here is a method that i use to train parry and it works very well.
since your friend is working parry i am going to assume he has a weapon skill (if he doesnt disregard the rest of my post)
ok so if he has a weapon skill do this....... go to an npc and buy a weapon your friend doesnt have any skill in. so if he has swords skill you would want a mace or fencing weapon, or if he has fencing he would want a mace or swords weapon, and if he has mace he will want a swords or fencing weapon. it can be either a 1 handed or 2 handed weapon as long as he doesnt have any skill in the weapon type. go to the sheep farm south of yew gate in trammel or fel (if you go to fel go at your own risk) and get 8 sheeps attacking you at once and tab out and just let them hit you. this is a good way to work healing at the same time so take plenty of bandy's, justlet the sheep hit you while you hold the weapon in your hand and stand there. you will gain in parry and because you have no skill in the weapon you are holding it will gain faster. i use this method and can go from 0-120 parry in roughly 5-6 hours. you can buy up parry from and npc beforehand also.