Value is not a convertible object

I have a simple query and Poco that I'm using with Dapper like so:

var jc = this.dbConnection.ExecuteScalar<JcUser>("SELECT loginid as Username,Password,coalesce(CustomerId,0) as CustomerId,TextProfileId,UxProfileId from \"user\" where id = @id", new {id = id});

Poco:

public class JcUser
{

    public string UserName { get; set; }

    public string Password { get; set; }

    public int CustomerId{ get; set; }

    public int TextProfileId { get; set; }

    public int UxProfileId { get; set; }
}

When this executes it throws an exception with the message

Value is not a convertible object: System.String to JcUser

The stack trace ends up at: at System.Convert.ToType (System.Object value, System.Type conversionType, IFormatProvider provider, Boolean try_target_to_type)

Any ideas why its doing this?

Thanks

UPDATE: Using var jc = this.dbConnection.Query<JcUser>("SELECT loginid as Username,Password,coalesce(CustomerId,0) as CustomerId,TextProfileId,UxProfileId from \"user\" where id = @id", new {id = id}).First(); appears to work. I also realise I'm a moron and ExecuteScalar is only for one value. However, is my update the best way to retrieve only one row?