Provided is an introducing system in which a server device introduces users of terminal devices to each other while motivating the users to join the system by presenting appropriate information to them during a wait time before they receive introduction. In one embodiment, the system includes an oil sump and an oil cooler that is integrated into the oil sump. The low-speed communication IFs are SDIO communication IFs and the high-speed communication IFs are USB communication IFs. A light reflecting portion 50 is formed on at least the light source overlapping portion DA.