Django How to Serialize from ManyToManyField and List All

I think what you need is the nested serializer:

class FollowerSerializer(serializers.ModelSerializer):
    username = serializers.CharField(source='user__username')

    class Meta:
        model = UserProfile
        fields = ('username', )


class FollowerSerializer(serializers.ModelSerializer):
    followers = FollowerSerializer(many=True, read_only=True)

    class Meta:
        model = UserProfile
        fields = ('followers', )

I used nested relationships in this link. Django Rest Framework Nested Relationships

Added a new serializer for only username of the user and also changed the other serializer.

# serializes only usernames of users
class EachUserSerializer(serializers.ModelSerializer):
    username = serializers.CharField(source='user.username')

    class Meta:
        model = UserProfile
        fields = ('username',)

class FollowerSerializer(serializers.ModelSerializer):
    followers = EachUserSerializer(many=True, read_only= True)
    followings = EachUserSerializer(many=True,read_only=True)

    class Meta:
        model = UserProfile
        fields = ('followers','followings')

Output was just what was I looking for:

{
  "followers": [],
  "followings": [
    {
      "username": "sneijder"
    },
    {
      "username": "drogba"
    }
  ]
}

Thank you for your help anyway :)