Puberty is an embarrassing, trying time for a child. Your body changes, you start to have feelings for the opposite sex, and more than anything, you are confused and bewildered about what’s happening to you. Tsubomi, Rea, Saya and a group of other fifth-grade students are being faced with this difficult event, and will experience the joys and horrors of it together. From learning about the difference between the male and female bodies, to experiencing a first kiss, to discovering the cause of pregnancy and even getting a first period, Tsubomi and her friends will finally learn what it means to be a grown up.
While Nayu Hayama may be a middle school student, she has the fashion sense of an adult – at least, when it comes to lingerie. Unlike her other classmates, Nayu is an underwear fanatic and is highly knowledgeable about a girl’s changing body, the right fit for a bra and a variety of materials like lace and beads. Alongside her new friends the busty Haruka and flat-chested Yako, Nayu will spread her love of panties and even help form a club dedicated to researching ladies’ delicates!
Both anime are about kids learning about growing up. Weather it's panties in chu-bra or the birds and the bees in Naisho no Tsubomi both give off a similar feel. Chu-bra is a lot more on the ecchi side than Tsubomi but if you liked one you'll enjoy the other.
While Chu-Bra is WAY, WAY, WAY more ecchi, both involve girls learning about their bodies and growing up. Equally as disturbing, but hey!
Fifth grade is a time for learning and growing and... getting into a whole mess of trouble! Class 5-2 is a "typical" fifth-grade class whose members always seem to be up to something. The leaders of their group are Ryota and Chika - Ryota's childhood friend who has a crush on him that she can’t seem to confess. While Chika continues on, remaining a close and valued friend, Ryota continues to be a typical boy who is oblivious to her feelings. Furthermore, he can’t seem to stay out of trouble with the ladies! Different situations keep their lives busy during school – everything from loose teeth to getting locked in the PE storage room. School is much more enjoyable when you are young and full of dreams!
Both OVAs are about prepubescent boys and girls exploring the opposite sex and sexuality. If you are beyond that age, which most probably you are, and want to reminisce those days where looking at hanged bra made you fluster, watch them :)
Both anime are about kids growing up and learning about the other sex along with their own as well. Both will make you remember what it was like to be that age when you were learning all about that stuff. Kyou no Go no Ni is slightly more ecchi than tsubomi but still check one out if you liked the other.
They are both about an innocent schoolgirl learning about sexuality-related things, though Tsubomi is a 5th grader and Kanna is in her first year of high school. Both shows also have a mix of comedy and seriousness.
Be advised that Koe de Oshigoto is a lot more adult than Naisho no Tsubomi.
Both series are also quite short: Naisho no Tsubomi is three episodes long, while Koe de Oshigoto only has two.