Tanabata is a Japanese festival originating from a Chinese event. You can read the details on the wiki page. Suffice it to say that one of the features is that people wear yukata (a summer version of the kimono), and visit shrines in order to write their wishes out on paper and tie them to tree branches to make them come true. It's typically celebrated on July 7.
When I visited Seiyu no Tamago, the customer seated next to me was trying to decide where to go the following day, Tanabata Day, to see maids in kimono. One of his choices was St. Grace Court, and I figured that this would be a good chance to check out something. A few months ago, a visitor to Maid Runner wanted suggestions for maid cafes to visit during their vacation in Tokyo, and I'd made up a list of names. When checking the websites to verify the list, the website for St. Grace Court came up as a broken link. It looked like SGC, which isn't on the beaten path, had closed. But, a little later, I encountered a dansou (woman dressed up as a priest) on Chuu-ou Douri handing out fliers for SGC, and I told her what had happened to me. She answered that the site had been taken down for redesign, and that the cafe was still alive and well. So, for Tanabata I stopped at SGC to see if the physical location had changed.
Actually, the cafe is the same as before. On the other hand, they did have some changes as part of their event. The main difference was that the "sisters" were all in kimono. That, and there was a small fake tree on one table with photos of the maids tied to the branches (the photos, not the maids, sigh). For 500 yen, you could take your pick of one photo. Normally, SGC doesn't offer "2-shot" photos (2-shot is the standard Japanese phrase meaning a photo with two people in it), but for Tanabata you could get your photo taken with a "sister" for 1000 yen (the 500 yen photos were "1-shots").
They also had a seasonal menu, with a curry rice plate for 1200 yen, or shaved ice with ice cream for 1000 yen. I decided to get the peach-flavored shaved ice and vanilla ice cream dessert and a 2-shot photo. The dessert was very good, but way too small for the price. Along with the 500 yen table charge, the total of 2500 yen ($27 USD) was on the very high side. Then again, it was a very hot, muggy day and the peach snowball felt really good. Plus, the maids were friendly. One other point is that this particular maid photo specifically included having the "sister" sitting at the table for 3 minutes touching it up. She even had a stopwatch out to measure the time.
Coincidentally, or maybe not, the customer from Tamago was also at SGC, and we were the only two in the cafe then. However, he was a lot less talkative to me, choosing to spend all his time with the "sisters".
Happy Tanabata to you.