@Kyoshi:
Because I absolutely love this game, I might be a biased source. However, comparing it to similar games or checking the features might help with convincing you whether or not to buy it. For example, this RPG has an emphasis on loot, similar to the Borderlands series. Also like Borderlands, it has a color coded loot system that lets you see if the equipment is worth using. This typically ranges from white (ordinary equipment) to orange (amazing and rare equipment).
There are currently 6 character classes, and they can be played as male or female.
Barbarian: Typical Warrior character. fights in Melee range, tough, can use giant two-handed weapons, or two one handed weapons.
Monk: Fast melee character. They're one of the best classes for healing and buffing allies, but they're also good at dealing damage too. Not tough, but not fragile either. Signature weapons include fist weapons or daibos.
Witch Doctor: Ranged caster character. They're so unique with their attack approaches that it's hard to compare them to any other class. They're great at weakening or debuffing their enemies, and they're great with inflicting status ailments such as poison. Can summon a good amount of allies around the beginning levels, up to a ridiculous amount of summons endgame. Their weapons are ceremonial knives.
Demon Hunter: Ranged Archer character. They can attack from a great distance, set traps, evade, and plenty more flashy tricks. Their defense isn't significant, but the devastating damage that they can deal is. They use bows, crossbows, or dual hand crossbows.
Wizard: Typical Mage character. They often attack from a distance, and their attack spells can have a huge area of effect. They have shielding spells, so they're not too fragile. Their damage is great, also.
Crusader (my personal favorite): Tanky melee character. With their defense and healing potential, they resemble Paladins from other RPGs. Can be very hard to kill, and they can make use of their high toughness to convince their enemies to attack them rather than an ally. They almost always carry shields, and they use flails.
this game's view is primarily a bird's eye view. Pretty much 100% of the time, you will see your character and the world around them from above. While playing co-op has more benefits, you can also solo (which is still fun). As your character advances through levels, they learn new skills and obtain runes to enhance those skills. Choosing a skill or rune isn't a permanent choice. You can switch around active skills and runes to form many builds. The same applies to passive skills.
The Xbox One version of Diablo 3 is a good choice, if you don't have a gaming PC or your friends prefer Xbox. Before I had a gaming PC, my brother and I played co-op on the Xbox 360 version of Diablo 3 (I strongly recommend against this if you have an Xbox One), and it was very fun.
Before you take my word for it, I suggest looking at videos of gameplay during the beginning.
TLDR: Diablo 3 has six character classes with their own strengths and weaknesses. Loot is always emphasized in this game. The gameplay is always in a bird's eye view from above. If you have multiple consoles, the one your best friends choose would be recommended. Avoid the PS3 and Xbox 360 versions; They are no longer supported, unlike the PS4, Xbox One, and PC versions.
If you have any other questions, I'll be happy to answer them.