As long as Kosei is enchanted, equipped, and has a counter on it, Kosei has "Whenever Kosei deals combat damage to an opponent, you draw that many cards and Kosei deals that much damage to each other opponent."

Equipped creature gets +1/+1 for each Aura and Equipment attached to it and has ward {2}. (Whenever equipped creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.) Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

No more than one creature can attack each combat. No more than one creature can block each combat.

Enchant creature Equip abilities you activate that target enchanted creature cost {3} less to activate. Aura spells you cast that target enchanted creature cost {3} less to cast. Enchanted creature gets +2/+2 for each Aura and Equipment attached to it.