Three years and 23 days late, but here's the raw for this comic: https://sai-zen-sen.jp/comics/twi4/buddhacafe/0036.html
The kanji for Shunkai's name is 春海. The characters mean "spring" (the season) and "ocean" respectively. An alternative reading would be "haru" and "umi," which Ruri converts to the very cute-sounding Harumi.