Sorairo Koiiro
From Intercross & Shoujo Crusade:
1-3. Sorairo Koiiro
Sora somehow ended up in a science class with all boys. Now, she's going to pitch in and help them enjoy school life by showing them her Girl Spirit!!
4. Sakurairo Koiiro
5. Sore demo Yappari Kimi ga Suki
The energetic and cute Rin is actually an otaku! Unexpectedly, she meets a 3-dimensional boy with the same looks as her beloved, Chris-sama! Otaku love in full bloom.