Kouhei Tsukushi
Tsukushi is a tall quiet man who is usually seen around Usui. He usually doesn't talk much and shows about as much expression as Sasazuka(that is to say, not a lot). Tsukushi is shown to be a reliable friend and pollice officer, being very responsible and punctual. He is very loyal to Usui, choosing not to accept a promotion just so he could continue working under him. Usui himself admits Tsukushi has a good eye for strategy and was impressed with his intelligence and upbringing. Tsukushi's favorite food is "Ginza Bulgarian Probiotic Rush" yoghurt. He becomes extremely displeased if he doesn't get his daily intake of the yoghurt, and humorously emits a dangerous and murderous aura, capable of giving people around him stomach aches. Tsukushi's daily morning routine is shown to be lifting weights, taking a shower, checking his paperwork, getting changed and taking his yoghurt. He has also been shown to be very allergic to chocolate, causing him to "get a face like an angel that has been shot down", according to Usui. In this state, Higuchi also describes him as "divine-looking". (Source: Neuro Wikia)