entity = (T)_nhSession.Load(typeof(T), id);

_sessionFactory = new Configuration().Configure("Nhibernate.cfg.xml").BuildSessionFactory();

<?xml version="1.0" encoding="utf-8"?>
<hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">
	<session-factory>
		<property name="connection.connection_string">Data Source=TEST;Initial Catalog=TESTDB;Integrated Security=True;MultipleActiveResultSets=True</property>
		<property name="dialect">NHibernate.Dialect.MsSql2005Dialect</property>
		<property name="connection.provider">NHibernate.Connection.DriverConnectionProvider</property>
		<property name="connection.driver_class">NHibernate.Driver.SqlClientDriver</property>
		<property name="proxyfactory.factory_class">NHibernate.ByteCode.Castle.ProxyFactoryFactory, NHibernate.ByteCode.Castle</property>
		<mapping assembly="NHModel" />
	</session-factory>
</hibernate-configuration>

using FluentNHibernate.Mapping;

namespace NHModel
{
    public class TestObjMap : ClassMap<TestObj>
    {
        public TestObjMap()
        {
            Table("TestObj");
            Id(x => x.ID).GeneratedBy.Identity();
            Map(x => x.ObjName).Column("ObjectName");
        }
    }
}