Shadow Wolf

During a stressful time in the Fourth Shinobi War, Hana Inuzuka and Shikamaru Nara were sent on a mission. During the mission, they slept together to help relieve some of the stress. After the war, Hana found out that she was pregnant. Both are heirs of their clans, so they cannot marry unless a sibling becomes heir. Both are young. Their child will be the the oldest of their generation.
(Naruto doesn't belong to me, duh.)