Kokoro Connect has 13 episodes plus 4 episodes in special type. The anime has 4 arcs (the last 1 arc is in special) with different phenomenon that is made by something called Heart Seed.
Arc 1: ヒト ランダム (Hito Random). Hito also known as “people”. This arc tells about Swapping Body at random.
Arc 2: キズ ランダム (Kizu Random). Inner Desire Unleashed. Saying or doing something on the order of the subconscious. No matter whether it’s good or bad.
Arc 3: カコ ランダム (Kako Random). Back to Childhood. “Kako” could mean “the past”. This arc make the main character back to children at random age. Making them remembering something forgotten.