Blue striped shorts guy is known as Mr Skin (or 皮長さん in Kanji - good for searching Japanese language sites). He is in a lot of the scenes in the Beauty and Phimosis series as well as other videos from SPC. Unfortunately, all mosaiced, as far as I have seen.
The girl in the 2 vids in the OP is Shirayuri Nana (or 白百合なな in Kanji). She is also in some of the Beauty and Phimosis series and has done a lot of foreskin-play scenes, also all mosaiced AFAIK.
This profile has a lot of the individual scenes as separate clips:
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I think that this seller on FC2 has some connection with the studio (or they don’t bother enforcing copyright). He has a lot of videos of different collections of scenes with a lighter mosaic than is on the DVDs or paid streaming sites.
It would be fantastic to see these uncensored (and translated/subtitled).
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