"Someone who you haven't seen much of thus far is Jenna, but just know that she is fantastic," Arie wrote in his People blog.
"Have you ever met someone who could always make you laugh? She's so funny, light-hearted, charismatic, quirky and sexy. I've never met anyone like Jenna before."
Becca received the very first one-on-one date of the season, and Arie has been shown admitting to the bachelorette he misses her when she's not around.
"It was nice to see Becca K. again after our one-on-one. Like I said earlier, I know it can be hard to be on a group date after a one-on-one, but that evening proved we hadn't lost our spark and were continuing to build on our already amazing foundation," said Arie.
Arie brought Becca and Chelsea on a group date this week in which they performed onstage with the "Dynamo Dogs."
"Chelsea was really amazing during the day portion of the date -- her mama bear side really shined through with the dogs," Arie wrote.
"That night, she really opened up to me and I started to see more of her than Chelsea, the super aggressive woman who pulls me aside first, or Chelsea, the mom. That night she reminded me why I find her so confident, kind and sexy."
And during the cocktail party preceding the season's third Rose Ceremony, Arie found himself wanting to talk to Seinne first in order to re-establish their connection.
"By the end of the night I'd have to say a couple hard goodbyes. It was important to me to pull Seinne aside first because she didn't have a date that week. Sometimes I don't put women on dates because I already have so much confidence in them and I need to give other relationships a chance to grow," Arie explained.
"After last week, I knew how much I liked Seinne. She's so beautiful, fun, smart and worldly. I missed her during the week and spending time with her was a great way to start the night."
Arie added, "One thing you didn't see was that she used part of that time to teach me some yoga. After a long week, I did my best to not just stay in child's pose."
And another "amazing moment" of Arie's night was thanks to Lauren B., who finally had her first kiss with The Bachelor star.
"This was the first time sparks really started to fly with Lauren B. I had been interested in her since the first night, but hadn't had much time to grow that relationship," Arie revealed.
"I also really enjoyed my time with [Tia Booth]. What better way to show her I was thinking about her than to bring the south to Southern California? I still prefer red wine to moonshine, but I loved getting to hang on the hay bales and talk about our feelings."