Ah! Confess Your Love Under the Moon?

Megumi gives Keiichi some tickets to a beach resort. Keiichi and Belldandy go, but the sisters tag along as well. Urd tells Keiichi there's an island spot where if he confesses it will be true love. Keiichi tries to take Belldandy to that remote island location, but Skuld has other plans.

Synopsis excerpt via Kitsu.