I would recommend Elephant Café in Harajuku, opposite of Laforet and next to GAP. It has an amazing interior and really cheap and tasty food. We usually came here as a group of 4-6 people a bit later in the evening, ordered a lot of different dishes which we all shared and tasted. The food is asian, kind of thai-style. We went here many times and also had a party here. Don't miss it!