Imouto sae Ireba Ii. (ONA)
Japanese title: 妹さえいればいい。
Type: ONA
Episodes: 6
Source: Light novel
Genres: Comedy
Studios: SILVER LINK.
Duration: 2 min per ep
Rating: PG-13 - Teens 13 or older

Original "chibi" styled animations of Imouto sae Ireba Ii. posted on the anime's official Twitter channel. Also included on the BD/DVD releases.